Walmart delivery is almost entirely done by a 3rd party driver that works for “Spark” which is a doordash/Uber type service and they are paid a base pay per delivery+ tips. If you aren’t allowed to leave a tip then the store you are ordering from actually utilizes in store delivery drivers that use a Walmart vehicle and are paid an hourly wage.
https://www.reddit.com/r/walmart/comments/16mwgma/are_delivery_drivers_paid/

