LOL! We're all so funny! I love it. It's amazing what ppl do!
I use my rubber shelf liner under cakes in the back of my Durango when I transport them.
I have a set of 4 little rubbery shelf liner-like mats that are round. I guess they're like the placemats, but way smaller. I don't remember what they were originally for.
I use them to get a grip on jars when opening and put them on top of the monitor to set the speakers on. One of those might work better under the foot pedal, well, not better, but you wouldn't need to cut it.

I need it anywhere I sew. Carpet in the bedroom and laminate everywhere else...it looks like hardwood, but it isn't....it's slick!
:D