1. The Tesla driver does NOT need to get out of the car (screw rain and bugs).
2. It IS a reasonable time (no need to sit in a diner and wait)
3. The mileage limitation is becoming less limiting (no different than making sure a long trip has a gas station on the way).
Whats the big deal with getting out anyway?
Also if you have kids in the car, it's convenient, it's like asking why are there drive thru's at restaurants, car washes, and atm machines.
Not sure that #1 applies to everyone...I remember on a road trip, in Oregon it's against the law for me to fill my OWN tank.
EDIT: Added wife's 2 cents
In contrast, I do see the value in having a battery exchange (it's something they can do better for me than I could do myself). In that case, not getting out of the car is still essentialy a non-factor for me, but it does end up being a tiny perk.
I have a hard time doing that with a car full of adults. (Though, to be fair, the cases I'm thinking of involved musicians.)