those aren't jsut any suction cups, those are sheet metal holders, and they don't slide, and are tested for about 300 lbs. Yeah, the pnematic might bend, but at that point, our robot will have fallen to pieces and we'll be out for good (that wouldn't be fun
)
Oh, and they actually work best on smooth materials like the HDPE.
<edit> We are more worried about this monster bending our robot's frame than we are of anyone else doing that.</edit>