Is the backplate prone to scratching off the grippy-gummy substance it's covered with topic

I don't really know how to call that coating and am not even sure if it's a coating or the whole backplate is made of the material that gives the grip. I just want to know if it's going to get scratched/scraped off by usage because this will pretty much determine if I'll get a case for the phone or not. I never had a case on my phone before and I don't really want one unless I'll need one. And I'll need one if it's required to keep my phone in perfect condition.