There are many more grades of animu fans than the two listed; it really is a gradient.
-There is the casual interest person, yes the one who flips through and likes the style but doesn't care too much. - censored/filtered stuff gets a lot of these people. The impression I'm getting from kumoricon is that they want to get most of these people.
-You get the dedicated person. They're familiar that the things come from Japan. They enjoy the style/stories/ideas and will often go looking for more where they can (movie rental stores, etc) - These people tend to be oblivious to the amount of filtering thats going on.
Then there are two variants of the next grade
-Pleasurable fan. These people really enjoy it, mostly get a little elitist about subtitled animu over dubs as they're appreciating the original voice actors' talent. These people will actively seek out other friends with similar interests. This is the point they find out how much is cut to make anime "Disney compatible."
-Weeaboo. These are the Lowest Common Denominator of the fan base. They're fans for the sake of being fans to be a part of a group of fans. They'll enjoy whatever the latest popular show is, then discard it when the next one comes along. They usually 'squee,' and yell and make it so that
everyone knows that they have the hots for Sasuke/Ed/etc. See:
http://www.youtube.com/watch?v=XP5lz2CYNR4 - These types know about the filtering and only care about seeing the unfiltered if it lets them look cooler than their counterparts.
-The Connoisseur. This is the fan that started getting into fansubs at the end of their Pleasurable Fan phase. They're getting into the technology of the day and actively hunt for the next best thing (how many of you were watching Haruhi a few hours after it initially aired in japan? Macross Frontier? etc). These fans are awesome because they're appreciative of the art and they will actively include Pleasurable Fan and The Dedicated Person in their group to share with. - Any filtering is nothing other than diluting a high quality product into marketable trash for the masses. So this person is a purist.
The end game breaks down into two groups again:
-The Professional (The Ascended Otaku)- This person
really loves the stuff. No longer just for the surface features of anime, but because of the origins of the story (Do /you/ know the original tale of Sadako? Momotaro? etc), the music that's used (introducing them to actual music besides pop), cultural nuances; the list keeps going. This is the person who has taken some Japanese. They are pretty likely to cook several japanese dishes. They have, however, lost some of their 'glazed' view of anime and instead of using conventions as an excuse to be an obnoxious brat, are very laid back (most convention staff are these types). The professional does not really interact with anyone outside The Connoisseur for sharing anime with. - Filtering anime for this group is seen as very wasteful. It isn't quite the blasphemy it is to The Connoisseur, but The Professional will skip buying a state-side release because of what was done to the product state-side. Instead they'll go download the copy they can find.
-The Artisan - This person shares most of the same traits with The Professional. Instead of becoming more socially inviting to others with showing product, this person went and
really did learn Japanese. They're very active in adapting their new skills and applying it to shows. They'll hunt out raw anime and cut their teeth on shows, just trying to figure it out. These people generally join fansubbing groups and start producing product for everyone above in this list. You get a very pure product, which is what The Artisan loves. They give their work away (along with someone elses'
paid-for works) in an unfiltered, unmodified, un-censored manner. As they get better, they dig into eastern philosophy (GITS:Innocence), cultural references (GALS!), technical discussion (InitialD/WanganMidnight/Capeta), Science (Moyashimon), and many more refined aspects of the language AND culture. These people are the anti-filter. They offer the purest form of the product for free. - Those who make filtered crap hate these people. It would be one thing if the filtercorps made a 1:1 product between the fansub (some do!) and the commercial release, but they often don't. The upper echelons of the fans have a decision to make: buy a legit copy of a show but know it's very inferior to the free product (and we know what the end result is, typically).
So to really answer the question now; like all things it depends. If you want to simply have a mass market full of the same kinds of people who would bully you in school, pick on you for being a nerd, or any person who tends to dislike things that haven't been refined into a McDonald's cheeseburger level of manfuactured simplicity, then you need filtering/censorship. The kind where a significant amount of effort it applied on the fly to say what is and isn't okay, done by several different people who have different standards each. (Anecdotal example that has been my experience at K-con: Guy in a brown bear suit? Hell no. Furry with a sign on his back that said, "yiff" with an arrow pointing down to his butt? That's just fine.) It is, in a way, very similar to Comcast's bandwidth cap. Some people get different numbers than others, and rarely are you told what criteria you're graded against. All that you're left with is a very sanitized product and most people don't lilke eating soap.
The other direction is how K-con was a few years ago, and how Sakura-con was back in 2000-2002 or so. It's a giant club. Everyone is pretty open. They'll try shows that they may well not like, or even be offended by (Hey, it's sailor moon! I love sailor moon! Why did this kid just drop his pants infront of ChibiUsa?... WHY IS HE WAVING ******** OH GOD >_< ) certain things. But these people exchange one or two irks for getting a great group of friends who share
most things. These are the people who gave Anime in the states momentum to even get on the radar of Cartoon Network. I wouldn't give CN credit for introducing a lot of good people into anime; those people would very likely get influenced by the good fans. Main stream sanitization trades off our quality product to invite the masses. Personally, I don't want the masses participating in what I enjoy precisely because they will influence the product I buy to the point it's garbage.