It's a compromise.

Option 1: Never permit vulgar language in public settings to satisfy people who are offended.

Option 2: Always permit vulgar language in public settings to satisfy those who wish to be vulgarly expressive.

Option 3: Use euphemisms and placeholders, so everybody gets something but not everything. Crucially, it signals mutual respect.

See, also, https://en.wikipedia.org/wiki/Polite_fiction

communicating that someone is upset while at the same time expressing that they're still willing to abide by the standards of polite conversation.

Using stars like this is like cursing behind your hand or under your breath. Expressing honest contempt but in a sort of distanced way while maintaining composure, in contrast to say a full on rant.