I'm pretty sure it'll make other stops. In my understanding, the only way it would be non-stop to WL is if everyone else in your bus/van is also going to WL.
How many of you are there? If four or more, you will find almost anything else more satisfying than the Mears Shuttle, since the latter charges per person.
For all, including Mears, you should reconfirm your ride back to the airport about a day in adv ance.
Mears is not all that bad. They try to group people going to resorts in the same area. It is not as fast as a towncar but will still get you there in a fairly efficient manner.