Only show cars are suppose to park on site. I don't know if a Pacifica (as a example) qualifies even though it's a Mopar. I have seen non-Mopar vehicles BUT I think they registered as vendors or maybe organizer's friends, or volunteers or some that are connected. So basically it's no if it's not a Mopar. When I go for the day with my Toyota, like this year, I try to find a spot on the nearby neighborhood streets.
Several vendors, probably all, will take US money just be prepared not to get the best exchange rate. I have a few American friends that go and am pretty sure they barter with US cash but I never actually asked them. PM member JEJJ, he's bought stuff there.
Being an out-of-towner too, I have no idea where a good place to eat is.