The rare times we've eaten at Cabanas, I've handed a tip (cash) to the servers. Not much, just a few dollars.
I did this because their service was over the top outstanding...not because I feel sorry for whatever their salary is, what they do when not there, how servers in the MDRs are tipped, whether they are in training (I don't know if that's true), etc. We tipped excellent service, and they earned it.