Alcohol and coffee are also helpful.

No, it's not. The most you can charge for a soda is $3 around here. Even if you make 95% profit ($2.85), pretty much every single food item will make far more profit. A $12 salad will net you $9, a $15 dollar pasta will probably net you $12, a $40 steak will net you $20, and so on.

Gross profit matters far more than profit margin. Also the best way to be profitable is to increase sales relative to fixed costs, rather than trying to squeeze every dime out of limited sales.