If you don't want to haul your quilt out to one of the places mentioned or don't want to spend a lot of time scrubbing their table (that would be me), you could get one of those plastic folding tables from HD or Lowes. I think they're on sale a lot in the summer for gatherings. If you don't like its height, you could add risers or set on a tall bed. Risers are super cheap at BBB. I just pinned one at chest height, using a combination of risers, and it was heaven.
I have learned the hard way about bending over a low surface to baste.
Hugs,
Charlotte