Oversize people, checking out of a resort

i have a question. But anyone here who is oversize and with southwest has to buy an extra seat, do you have issues at the resort w/ checking out?
Disney offers the option of checking your baggage at the resort, getting your boarding ticket, etc....but everytime, not some times, but everytime I check out of a disney resort I'm told they can't do it, and it has to be done at airport. My sister and brother and their families, my gf, son, friends have never had an issue. So the only thing i can think of is because i have 2 seats on SWA. Anyone had issues?

This has been my daughters experience also. It is my understanding that they cannot print out the extra reserved seat ticket.