NC for this, as I've posted quite a bit in my old name.
I'm a teacher in a relatively small school, with approximately 55 teachers / TAs / office staff. I've worked there for 15 years, and it's always been a cliquey place - social events arranged in secret etc. Membership of the clique is both male and female, and all ages. It isn't long-timers; new staff get invited to join by some mysterious process as the other members decide they are suitable. If non-clique people go to the (few) social events that are properly advertised to all staff, we are subtly made to feel unwelcome & generally don't bother going again.
There have recently been some milestone birthdays amongst clique members, and the clique has made a huge fuss about these - banners, balloons, tiaras, photos of social events with lots of "Oh it was so funny" type stories. Naturally, this has just emphasised the division between the staff. A very long-serving teacher (who is actually a lovely person & would be devastated to know people felt this way) is leaving in the summer, and the clique organised a leaving do for them on their invitation-only WhatsApp group. This was discovered, and protests made that everyone should be invited. There's now a What'sApp group called XX's Leaving Do, which non-clique members have been invited to join. However, it's blindingly obvious that it isn't the main WhatsApp group, and has been created to fob us off. Should we (a) say nothing and quietly leave, or (b) say "Are you sure you've added us to the right social group? There don't seem to be many here 🤔"
Thank you if you've managed to get to the end of this! I realise that it's ridiculous to be giving it so much head space, but it is bugging me. I really don't see what's so bloody difficult about putting a notice up saying (for example) Everyone welcome at the pub after work on Friday.