The way celebrities interact with service people,waiters,waitresses, etc.,can tell you lots about their character.
For example, people love Kate Winslet. And for good reason. She typically leaves a 50% tip.
Blake Shelton once left a $50 dollar tip on a $16 dollar tab.
In the days of restaurant smoking sections, John Goodman tipped a server $100 dollars when the server lit his cigar.
Check out other celebrity/service person interactions here.