What would cause a Varathane EZV sander to rip the sandpaper?
If the ripping is always happening in one spot on the floor take a really close look for any nails, tacks or even screw heads that might still be protruding. It only takes the slightest thing like this to rip the disc given that it's spinning so fast.

Carefully go over the floor either pulling the tacks out or using a punch to drive the heads of the nails a few mm below the surface.

If the floor is screwed down anywhere it will be a good idea to remove the screw, use a countersink bit on the hole and then replace the screw. Again this should be a few mm below the surface.