Pass-ed

Is the -ed ending for past tense fading into history? Judging from common misspellings you see on signs, it seems to be. Down the street from me is a sign that says "boil crawfish". At first I thought this was a south Louisiana thing, but I've seen it other places, too. Is -ed going to be a thing of the past? Of the pass-ed? And does the word past come from the word "passed". Must check on these important bits of trivia.