nah, they're not getting a tip while charging me $3.99. that's more than my meals cost when i go there half the time
Delivery services that deliver anything take-out for you, like Favor and Postmates, charge about $5 in fees and usually add an additional $5+ in suggested tip for the driver (all of the tip going to the driver). This adds about $10 to the cost of your food, but you have the benefit of getting anything at any time and, as opposed to something like pizza delivery, your delivery driver goes straight from the restaurant location to your residence, usually waiting there for it to be ready to take, and isn't multitasking with other orders, so your food is as fresh as it could possibly be.
Tip the driver properly or don't use the service. It's how they get paid for their work. I suggest not using the service in this case, because five minute old Taco Bell is already turning into mush, and these markets all have proper delivery services like I described above for better food choices.