I don't get that happening on this bike but then I tend to ride in motocross style boots ... have had it on others though. I have seen something on here relating to that. In general I tend to make sure that my riding kit is all snug and secure and that nothing catches. It's something we get hammered into us on a daily basis .... anything that can be caught will be caught.
Your just going to have to get rid of your bell bottoms. I only wear a pear of Dragin Jeans or my Klim pants over Sidi Adventure Rain boots and I have never caught those on anything.