This is a controversial topic, but I feel it's ok as long as everyone remains civil about it
@George
I feel like that sort of mindset could be said about a lot of things. The idea that "X is not socially acceptable behavior, without an event, therefore doing X within an event is bad for the cause"
Dressing up in a fursuit is not socially acceptable, people think it's weird, it's not fair to the public. We should stop furry conventions then. (Public walks and stuff)
Cosplaying is not socially acceptable, again most people would be confronted by it, so again we should not have anime conventions and such.
In some places in the US talking against god is not socially acceptable, it's confronting and attacks their beliefs, we shouldn't have atheist talks or meets then.
The thing about gay pride parades is they're not generally pushing for rights, that's what protests and stuff are there for. Gay pride parades are there for LGBT people to have fun, just like furry conventions, anime conventions and so forth. There was a thing in society where people were once oppressed, once told they were bad people for being them, so some people responded by saying "Nah, we're not bad people" and started telling other LGBT people that they weren't bad people and that's where the gay pride parade started. Now it's developed into a thing where it's like "Be proud of yourself, don't be ashamed, and have a lot of fun". So LGBT pride parades are more for having fun, and while it may not be socially acceptable to be provocative and let loose in this way, I don't think that means it should be stopped, otherwise we'd have to stop a lot of things I'm sure a lot of you also find very fun.
EDIT: Also I want to mention that gay pride parades are actually quite socially acceptable now. LGBT Mardi Gras has a lot of straight and non-LGBT people participating, volunteering, watching, partying, etc. I would say Mardi Gras has actually increased peoples "like" of LGBT people more so than decreased. Mardi Gras are events that are held all around the world, not all are LGBT based, but they all have a common theme overturning social conventions (read wikipedias definition on it) and people enjoy them.