The reasons why a person would not want to witness such and exchange doesn't matter; Whether it's because they don't want their children to see it or because, like me, it's triggering.

I'm not sure why you quoted the bit about the sign and not the bit that's relevant to unwanted witnessing of events.

As I said, some people will be deeply disturbed by seeing two men kissing in public. And that does not mean that boys shouldn't kiss. The 'right' of someone to not have themselves and their children 'disturbed' does not extend to forcing others to behave in a certain way.

Many conventions are and have always been sexually charged arenas. Not all of them - single-day non-costume conventions are generally pretty straight. If public sexuality is disturbing to you it's probably a good idea to pick your con wisely. (And avoid furries. :) )