The shifter peg is on a spline (or something like that). The screw can be loosened/removed and the peg pulled off and positioned higher for bigger feet/boots.

Or, try western boots with a narrower toe. I use these on my Harley with good results.

And .. many manufacturers make lowering pegs of some sort ... I have them on my Wing. This will give more room for your BIG feet, m'friend.

Just some suggestions.