“Everyone was doing it” explains how it happened. It doesn’t explain why you did.

A crowd is a real force and it is not a decision. Describing the setting tells people something true about the pressure in the room, and it leaves out the moment where you looked at what was happening and went along with it. Those are two separate facts, and only the second one is yours to account for.

Next time you reach for the context, give it and then say your own part in the same breath. That it was the whole group, and that you joined in anyway. The second half is what keeps the first half from being a shelter.