You mentioned that you live in southeastern Michigan, which might explain it. Depend on exactly where you live, you may be on a peripheral area between the "General American" accent and the full "Upper City Shift" accent. Some more maps from the website I had linked to:
I just listened to that youtube video you linked, and I agree with funnyhat. I'm from southwest Michigan, the Kalamazoo area, supposedly the very heart of the NCVS region, and I also thought the samples of that woman talking, where she pronounces "busses" like "bosses," sounded very strange, and not at all like how people around here talk. I should have listened to it earlier in the thread, cause funnyhat's right.