Million dollar question. Where did HUT come from?

[Rain Man]

I think the real question is where the word 'hike' originated. Based on linguistic theory, it's pretty easy for me to theorize that 'hut' is merely a shortened and more gutteral version of 'hike', and that it probably evolved for two reasons - it's easier to yell, and it's a logical evolution of a word that requires more effort to pronounce correctly.