The sad answers are "very few" and "it probably won't", respectively.
I have a few friends who work at dealerships and the deal is you bring the tools you work with. For most guys, that means if they have to adjust some customer's lights, it means pulling out the screwdriver and nothing else. If they wanted to aim someone's lights with an optical aiming machine, then they'll just have to buy it, since it's not one of the few tools the dealership provides (the dealership provides the heavy machinery, like lifts and hoists, but little else). And they've been getting a lot of requests lately for headlamp "reaiming." The common complaint is that the customer has experienced people "flashing" them at night, so the lights must
be vertically misaimed. The reality of the situation is likely that the customer hit a speed bump while driving their 2020 model with the LED lights, someone else thought they had been flashed, and responded in kind, and now the customer is getting their lights tampered with randomly.
I can't help but wonder if one of those Bosch self-leveling, cross-hair projection laser tools that anyone can find at Home Depot/Lowes would substitute for an aiming machine. Park the car 25 feet back from a wall. Put the self-leveling laser on the tripod and extend to headlamp height. Turn on the laser, boom, instant cross-hairs on the wall as a reference for aiming, and the laser is self-leveling, so it's probably better than assuming the floor is flat.
In your opinion, would this be an acceptable substitute for an aiming machine? These self-leveling lasers can be had for a mere $35. I could see a dealership tech shelling out $35 to better aim lights. Shelling out the $$$ for an aiming machine for customers' cars...maybe if they won the lottery. There's likely a case to be had in time savings: it's likely quicker to turn on the laser and have some cross-hairs on the wall instead of driving the car up against a wall, marking the height of the lamps and connecting the dots, and then backing the car up.