Another important conversation to start: a billion is a THOUSAND million. IPOs create tsunamis of wealth not even requiring greed - just a sense of entitlement.
Always tip in cash, and be generous. Why not? Especially since you've taken care to get it directly to the person who did the work!
No need to use anything. Stick purchases in your briefcase, purse or pocket. Or just walk out of the store carrying a few items - - and your receipt, of course 😉. If you need a larger bag, reuse anything that’s already been created and then use it again and again until it falls apart. Repeat.