They do, and it does provide a small boost to the frontline staff's income. But as someone else said, that's not the guest's problem. If we can help a guest and ourselves at the same time, great. If the guest has already helped themselves, we're happy to still take care of bags, a bottle of water, whatever...and set the next person up with a ride.

FWIW, the hotels I worked at had lots of return business, and the drivers we had agreements with always charged the standard flat fare to the airports, whether we called them or not, so it was all the same to the guest (this was pre-Uber). The kickbacks came into play because the drivers wanted us to call them instead of a competitor. We had a fair rotation between the drivers that gave us the biggest kickbacks, and would call those with smaller kickbacks when our "A-Team" was already occupied.

And before people jump on me for just hooking people up with the drivers that paid us the most, we frequently turned down drivers and car companies that delivered poor experiences or showed up with beat-up cars. There was enough competition for us to choose on behalf of our guests, and many of our drivers would give us additional kickbacks when guests requested them specifically again on the next day or during their next visit.

I've never tried the remote pin trick, though I've heard it works. Curbside pickup at most airports requires that the driver have an airport livery permit of some sort, which is why only UberBlack is available and not UberX on airport properties (at least where the livery permit applies).