Well, as a current driver for Dominos, I feel the need to chime in here on the delivery charge. Personally, I hate it. I hate it because people assume that the delivery charge is a tip. This is not the case though and I'll explain more down below. I do agree with you though on the price of doing business. The owners I work for are very cheap. We charge a check charge because the bank charges Dominos for each check. That is just an example of how they pass on every little bit of charge they can on to the customers.
I personally apologize for the guy who gave you an attitude. I try to treat everybody the same no matter what they tip me. The fact that he gave you an attitude over the tip shows that he doesn't understand what a tip is. A tip is a monetary show of appreciation for a service provided to you. Its not something to make up for wages nor is it something anybody is "entitled" to. Its the customers perogative.
Actually, you are not 100% correct about that. At least thats not the way it is with Dominos. They might want you to see it that way, but the fact is, drivers were recieving "mileage" before the delivery charge was created. Pizza places didn't create the delivery charge to give the drivers mileage. The two are not related. The $1.50 that Dominos charges goes to Dominos. Then at the end of the night, when I check out, Dominos pays me mileage. You could say part of that delivery charge went to pay mileage, but you'd have equal claim to saying that part of what you paid for your pizza also went to pay my mileage. And if the delivery charges went straight to the drivers, I'm not sure if they'd be able to charge tax on the delivery charge. See it is actually $1.62 not $1.50 that you are paying extra because of the $0.12 in tax on top.
As far as what mileage is, I personally recieve $1.00 for every delivery I take. Some of the newer drivers get $0.90. In the case of tonight, I took 25 deliveries. This means I was given $25 mileage to cover gas and wear and tear on my car. Fortunately for me, I drive a car with decent gas mileage, so I only spent about $18 dollars on gas giving me a net of $7. Other drivers aren't so lucky.
The thing is, that mileage doesn't really have anything to do with tips. If the fact that I use gas is the reason you choose to tip drivers, then you might as well stop tipping waiters and waitresses. Unless of course you tip them because of how much money they are paid an hour as opposed to the service they provide. And if you want to go down that avenue, there are only 4 drivers at my store who make the current minimum wage. The rest of them get paid less than minimum wage because they are tipped employees. The law doesn't require them to. See, employers pay less because of tips, not the other way around. Your choice to tip shouldn't have anything to do with how little the other person makes, but on the service they provide.
In summary, I would hope you don't choose to tip based on how much gas I may have used, but on the level of service I provided. And just because there is a delivery charge doesn't mean you are being charged a tip, after all, that would defeat the idea of what a tip is.