Admittedly, my feet are bigger than most, and I am 6'4" and 280lbs, but even so, 'patty' at around 6'5" and 500lbs still only had a 14.5" print.
I also noticed, that with the exception of the big toe, all my toes look the same size - infact, the little toe actually make an impression of the side of the toe, which makes it look the same size as the others, and on a fairly even slant (probably down to ill-fitting shoes)
It goes to show though, that the human print is completely distinguishable from a BF print because of the arch of the foot - even someone fairly flat-footed like me has a prominent arch in the prints, even if (as in my case) the overall shape of the foot is very similar.
There are of course a few other differences that distinguish my prints from those of BF, but I thought the size was interesting - obviously 14.5" is at the small end of a BF print.
Apart from anything else, I got a brand new avatar out of it !