U.S. Clubs

Forgive my ignorance in this question, but I'm curious...
In the U.S., do the clubs provide instruction for free, or paid? I
know the commercial operators are paid, but I don't know about the
clubs. Probably depends on the club, I would guess.
I'm in Canada, where the clubs all teach for free; I'm not sure we
even have commercial operations (the clubs all sell introductory rides
with a day membership).
I'll eventually get some flying done in the States... just have to
convince my wife to let me bring the mistress along... or travel
without her and the kids