Like everything, I'm sure it varies store to store. I googled your question about splitting tips and this is the first hit I got:
https://consumerist.com/2010/03/30/4-myths-about-tipping-from-a-former-pizza-delivery-guy/
From the article:
"The driver just has to grab orders, deliver them, and collect the cash. It’s hardly a job worth a tip.
FALSE. Drivers are the grunts of the store, and do every job inside it. We clean the store at opening, fold boxes, make orders, take orders, box orders, proof the dough, make the wings, mix the sauce, load the freezers, cut the dough, unload the truck, balance the register, clean the counters, mop the floors, wash the windows, empty the trash, and get everything ready for the next day. In fact, drivers are the last employees to leave behind the manager on duty, and the first to arrive to help with the daily chores. Combine that with low pay and the fact we still deliver your food, and we work harder than anyone else in that store sometimes."
Yes, this is one guy's experience and like I said, I'm sure it varies by location, but it goes to show some delivery personnel are doing a heck of a lot more than just walking pizza to your door.
People have all kinds of reasons for working out what they think is fair tip compensation depending on the service received and that's fine. What I was addressing was the misconception that no work goes into carry out/delivery orders. Sure, they're not performing brain surgery, but it is more time consuming than just walking it to the door.