notbitcoin is saying the stuff they've ordered is unprinted. I'm making a new order at work, so we'll see if they're still doing it. Yesterday I looked at the stuff we currently have deployed, and the markings can be scraped off for the most part. So either way, it's not a big deal.
Yes, I've found that printing on the EPDM from McMaster Carr comes off with IPA pretty easily.