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I can't tell you how often I hear someone want to "ax" me a question.
I recall my linguistics professor saying the "ax" actually is an older form of the word that has been preserved. So it's not so much improper as much as it is antiquated.
Also, languages go through regular mutatations, this is just another one of them. I don't think "ax" is any different than "pail" vs "bucket" or "pop" vs "soda". It's just that it is associated with a poorer demographic, but that doesn't make it any less valid English.
PS- Yes, I am the kind of person that will use "thee" and "thou" if necessary to disambiguate from "you".