That might be the case, retrochic, although I suspect that Gay Pride events don't make people who were otherwise "positive towards the gay community", whatever that means, would have their minds changed. If you have a negative attitude towards gay people then it seems to me that only if gay people were to pretend they didn't exist would people's attitudes change -- and then, only because they no longer had to think about it.
Gay pride events are for the people involved, and as long as there is any sort of negative stigma about someone simply for being gay, then those events are necessary and should continue. And it's a real shame, then, that Gay Pride remains necessary.