If tipping is about service and the amount of work somebody does for you..........
Then surely the trouble of making a pot of tea with all the stuff on the tray and the time it takes to prepare deserves a far greater tip than pouring a measure of very expensive Brandy into a glass?
Brandy at $30.00 a shot = $4.50 tip - Time taken - 10 seconds
Tea at $1.50 a pot = $0.225 tip - Time taken - 5 minutes (usually we've found)
So, one customer who orders tea often and tips 30% is tipping well but the person who orders Brandy and does not create work 'gives' an excellent tip.
Therefore the crew member does not want me to drink tea. In this case, if I order tea the crew will hate me. They only ever want to serve the person who orders the Brandy etc.
Take this one further step........... crew members do not have your health as their prime interest. Infact, provided you don't cause a problem, they'd prefer that you drink yourself to death (later) rather than be sedate and healthy.
So can we narrow this down to tipping a lot is bad for your health?
Ps. Please don't throw things at me. I'm just raising a topic.