The same thing was happening to me. I installed DSP footpegs (not for that problem) and I noticed that it never happened again. I also lowered my brake lever to a point just slightly below parallel with the foot peg. I noticed I was accidentally dragging it a lot and was also nearly killing my bike in the air by tapping the brake pedal accidentally without the clutch in. I don't know if lowering the pedal height changes the angle where your boot is getting stuck, but take a look. Also, you might be able to see the spot on your boot that is hanging up and file it down a bit.