You tip the wait staff at a restaurant, as well as bartenders, taxi drivers, hairdressers and takeout delivery drivers.
So why not tip your flight attendant?
If you have recently flown Frontier Airlines, you might have noticed that on the tablet where you buy in-flight food or drinks there is a spot to leave a tip for your flight attendant.
Frontier seems to be a pioneer on this one.
Flight attendants with United Airlines are not allowed to accept tips and American Airlines crew members are instructed to decline tips.
Southwest Airlines flight attendants are allowed to accept voluntary tips if the customer insists.
Frontier staff used to pool the tips but now they are individually accepted and encouraged.
Frontier Airlines has introduced a tipping system for its flight attendants