Budget rental - airline mileage credits

I rented a car from the Budget counter at Rio (with advance reservation by the way). I never received my SW air credit for the rental so I wrote them and sent the info. They sent me a nice letter back but again I never received the credit promised within 90 days.
I finally call them and find out - no credit for off airport rentals! I sure wish I knew this upfront or even after I wrote them. What a waste of time and effort.
Not a big deal, but I do not like the way they handled it. Plus, they never returned my Customer Service email on the subject.
DaveOKC