I've been doing a bit of travelling for work recently, and have noted an odd and I think statistically unlikely occurrence - on 80% of the flights I've taken, I've been seated next to the wing. The exceptions are on a certain budget airline (no advertising here) who don't pre-allocate seats, where I've been able to grab a spot away from the blind area.

Even given that window seats are only a one in three chance, why can't I ever get a seat away from row 15 or so? Is there some sort of airline database that automagically allocates mid-plane seats to certain people?