I am not anti alcohol, whoever wants to, cool as long as you know your limits and don't drive cool beans
I just rarely drink (even when I am not peggers which changed it to never drink right now), I do like the odd sip of a friends mixed drink or a special occasion trying a drink, or experimenting with cooking, but really it just makes me act like I do when am sleep deprived which is really dyslexic and I can do that for free, I would rather have a soda and true you don't need it to have fun, and its spendy.
That said besides the drunk in con space not okay. It is not a good idea to drink at con. It lowers your guard and while people you just meet seems nice, you really don't know them well.
You might say, "well I will be with my friend who never drinks" Okay, do you trust them with your life? Cuz that's what you would be doing. And if your friend is drinking then they don't count.