Your mileage may vary on whether Sakuracon is being too cautious, but FWIW, they're not doing it to make attendees unhappy... they're trying to protect them, as well as the convention itself. A convention one state away recently had a police officer threaten to bring in SWAT, because he decided an obviously nonfunctional prop with an orange tip was a terrorist threat.
It's sad and dumb, but it's true. A police officer who's having a bad day and wants to give someone else one won't know or care that it's a perfect replica of Yoko Ritona's sniper rifle, that's it's made of PVC pipe, or that it's peacebonded. He'll just see you as "threatening", then as "disrespectful" for making him look dumb. And while you'll probably eventually be found not guilty, that won't give you back the time or money you lost proving it.
