I delivered Chinese food in 1965. I was paid minimum wage of about $1.30 per hour plus tips. The tips would generally make up about one third of my total pay.
You get to be pretty good at fumbling with change in order to maximize tips. You carry a lot of one dollar bills. You don't want to hand a customer 35 cents plus a five dollar bill in change unless you really want a 35 cent tip.
The total purchase price was key to getting a good tip.
It was terrible if the total bill was $9.35. You're getting a 65 cent tip. Much better if the bill was $8.70. Then you got $1.30, twice as much.
I give delivery drivers 10%.
Where? Sounds like NY or San Fran! lol