Even when I had a tent with a super-lightweight silnylon floor, I didn't bother with a footprint. The floor took no harm either from the ground or from my dog's claws.
Generally, the floor is the least vulnerable part of the tent. However, I do recommend (from experience) that you not pitch the tent over a mouse hole!
The mice would be not amused either.
If you have dogs in the tent, you could cut and file their claws, and put a fleece blanket on the ground sheet.