It’s your assumption that they’re trying to broadcast their heilgkeit. Why aren’t you dan l’kaf z’chus that they’re trying to be mechazek their kids (or themselves) in trying to uphold higher standards against the tide?
The fact that people only want to daven in “THAT” shul is very likely because they daven better, there’s less talking, or a better environment. The fact that they only use “THAT” hashgocha is likely because they have higher standards.
I’m sorry if you’re encountering people who are being baalei gsavah about their standards of frumkeit, but it’s so unfair to generalize.