I think I get what the problem is, but have you reached out to Walmart and asked them about the mandatory tip, along with how it's distributed to whom? FWIW I figured easy enough to look at their T&C's since I get spammed with a popup for that any time looking at walmart.com. LOL nothing there. Not even when clicking to see the "long" version nobody ever reads. Keyword search for "tip" = 0.
Not being argumentative, as I wouldn't be happy with that discovery either. Maybe not for the exact same reasons. I'd see it as a way I'm being fleeced for a couple extra bucks without any choice in the matter. If it's truly a tip, then put it in a free text field where I can choose any value, even if it's pre-populated with $4. If it's not a tip, then just call it a service fee or something, instead of deceptively line-iteming it. Papa Johns lets me choose that on the tip line, so should WM if they're going to stick it in there.
Regarding the transport side of the debate.. I currently have a motor carrier authority since 2011 and have been recently hauling Amazon trailers around. I've also delivered loads to many Walmart distribution centers. So not "insider" wisdom like a current or former employee, but seen enough under the skirts to draw a few conclusions.
Walmart Transportation is the subsidiary company that holds their interstate operating authority. Next time you see one of their semis in traffic, you'll see that in smaller lettering somewhere on the side of the cab, next to their DOT number. That driver is a Walmart employee. WM also contracts with other carriers, and you'll see them clearly marked in their native coloring and stickers, hauling the Walmart trailer. From what I gather, the WM private fleet does most if not all store deliveries whereas the contract carriers typically handle loads between DC's and from primary suppliers.
It gets much more unclear when talking about final mile or package delivery, since those (usually smaller) trucks usually never leave their state.
@Onyrlef Texas does require intrastate authority, so they would be required to display a company name and DOT number on the vehicle. So that "Walmart" delivery van may not be owned or operated by them. I can't say for sure, since I don't contract with WM like that for personal experience.
However, I do know for fact that Amazon does it. I've spotted many AZ blue day cabs in traffic and at their distribution centers that appear to be company colors, until you notice the different company name and DOT number in small lettering where it isn't as obvious as the expected Amazon graphics all over. Best I can tell, these are carriers that are exclusive to Amazon, or at least have a designated fleet serving them, to have the right/privilege/requirement to run trucks that look like that. If Amazon is doing it, probably fair to expect their competition is also doing it.
I bring you this wall of text to explain some of what you see, and possibly didn't notice. Or maybe look for next time you're out and about and see one of these delivery trucks out in the wild.
Another interesting data point was a separate discovery that popped up in my Youtube recommendations a while ago. The guy doing the video is a Spark driver in Arizona (seems similar service as DoorDash or the like) complaining about other contractors scamming the service, consequently reducing the available deliveries for legit drivers like himself. Meanwhile, Walmart and Spark doing nothing to curb it. The main point in bringing it up is: these are the guys doing grocery delivery. So Walmart does use contractors, at least in some markets.
I think it's fair to say that Bentonville gets farther away from their roots every year.