I never get unfriendly Thais much at all except in a busy tourist spot. Must have met 1000 and very few nasty. Some of the nicest Thais I've ever met were in places like Korat. General kindness no money involved.
Last night I went to a night market and you get different vibes off people. 50% to 60% of farangs are fine but 40%+ are angry about something.