.I have never been in a shop where the mechanics offer to take people home. You either get your own ride or sit and wait
Dealerships actually get reimbursed for "courtesy transportation" from the factory if it's a warranty repair. Otherwise it's just good business.
I have managed a few dealerships and a couple collision shops. My goal was to always keep the waiting room as empty as I could.
We had "porters" not mechanics that would shuttle customers. If a porter was not available, I would grab who ever was the least busy at the time. Once in a while they jumped out of the bushes!