Pittsburgh has the slang term “Yinz” which is used like “y’all” and I’ve taken to using the singular “yin” for a gender neutral replacement for “guy” in the phrase “my guy”, because “my yin” still carries that condescending tone that’s vital (to me, anyways). Not telling you what to say or anything just fun to come across some grappling with the same language problem

You’re right, I made the same mistake as OP. There is no “European system of tipping”.