Did anyone suggest that DMs should not be tipped? If so, I missed it.I’m surprised so many Americans can be so obtuse and act surprised about tipping. You tip your cab driver for getting you somewhere safely. Tip your fishing boat captain if that put you on the fish.
FWIW, I generally do not tip cab drivers on Cozumel but I tip the crew of a fishing boat the same no matter what the day's catch was, and I do tip restaurant servers. One thing, though - I do not buy into the idea that servers and bartenders "deserve a raise" from the traditional 15%; I have seen "suggested" tips at bars and restaurants as high as 35%. Servers already get a raise every time prices go up, and they have gone up a lot in restaurants over the past few years.