To be fair, this was the case in my secular(-ish) public school as well and I believe it was there until the early 2000s. The catholic church has many sins (which Squid did a great job laying out above), but I don't think they, as a group, endorse the concept of corporal punishment like they do with anti-choice practices or the rampant pedophilia. That's a cultural issue with certain regions of the US.