To be fair, a more apt comparison would if they were all sent to a car dealership, and the dealer was told they will all buy a car and just need help picking a color. I'm sure they'd get fantastic service.

Having said that, Apple is pretty well known for offering great customer service, even when it's clear you're not purchasing anything.

I've been in that situation at a car dealership and the service was pretty poor (AAA pre-negotiates prices with many dealers; if you call in advance you get the car at AAA's price without haggling). Basically, they know you're not going anywhere else, so they don't feel any urgency. It was much less stressful overall, but not because of the service.

Just an FYI. I don't know that the innate economics of Apple are any different.

AAA, Costco, etc. are all nice for having pre-negotiated prices, but IMO the best way to buy a car is something like CarWoo -- that way you might actually get a "deal" if you pick the right make/model, vs. a global price. I'd use them for my next car except I plan to either get a used diesel truck or a Tesla, and they only do new cars (and probably not Teslas).

(Although the absolute best deals I've found on cars have been deployed military BMW/Audi sales programs)