And soda is their big money maker since it’s so cheap to make. A gallon of syrup and carbonated water.
Fill the cup at least half way with ice and it goes even further.
Which is why I always tell them NO ICE and fill the cup..I put ice in it when I get home but usually don’t need it.
Every fast food “restaurant” I know of in California has self service drinks - they’ll hand you a cup and that’s about it.
Come to think of it - they now all have ordering off a kiosk as well - and/or they encourge customers to order online.
I think the ice costs more than the drink.
Mrs L worked in the banquet industry. She used to say the cup cost more than the soda they put in it.
L