The pizza places around here add a delivery charge, but the driver doesn't get it. So, those who think this is going to the driver are mistaken. Many don't tip because they think the driver is getting it.I stopped getting pizza delivered back when they added a fuel charge about ten years ago. I just order and pick up on my way home. I don't know if they even still have the fuel charge but my habit has changed.
Most places also don't pay for driver's mileage, so all deliveries (gas, car wear and tear) are borne by the driver.
My DS used to do this, but with the lack of tips, he quit.
Once, he was hired to be a delivery guy. He worked one night for little to no tips and he got back to the place to clock out. They wouldn't let him leave until he cleaned the bathroom for them. They weren't nice about it and the bathroom was a mess with various types of "mess." He quit after he did that for them and said, "never again." We almost had to get our attorney involved to get him paid for that night of work. When he finally told the manager that she'd hear from our attorney, they paid him from the register.
Delivery is a thankless job and for all the people who do this for us, I tip well. I usually don't go for delivery because I can get it sooner and hotter if I pick up myself, but when I don't feel like going out, I tip the driver well.