I was surprised to see how restrictive "Angel policies" can be when I finally found out what they were (how on earth is anyone supposed to know what an angel policy is if they've never heard that term before?!) I had no idea that some stamp makers might restrict a person from *masking* or using an incomplete image, which just seems utterly ridiculous to me. (Especially since some a-hole a few years ago printed giant pictures of other people's awesome Instagram photos without their permission and sold them for thousands of dollars and that was judged to be "fair use" - how can someone masking and partially stamping an image to create a new artwork *not* be considered fair use too?!)
But anyway, I sell cards, and no, I haven't been too worried about it. I would hope that none of the major stamp companies would waste their time going after my tiny unprofitable business that doesn't hurt them in any way (even if I haven't actually read their policies -yes, I probably should...)
Do you have specific images in mind? What does the policy specifically say? I do refrain from selling certain cards where the images came from digital files sold by other small businesses that clearly state that they can't be used in products for resale. I checked with one company I am friendly with and they said if I bought physical cards/die cuts/stamps I could do anything I liked with them (cut them up, paste them together, etc - obvs not photocopy them and sell them!) but the digital images are only for personal use.
Stampin UP requires that you credit them on the back of the card. With their logo stamp. Not an image of the logo. Not a photocopy of someone's stamp. Their actual stamp. That comes in an $$ kit of stamps. Which you must purchase all together. Uh huh. OK.
ETA: I did find in their policy that you can use digital copyright from some software program of theirs that THEY NO LONGER SUPPORT. Last I checked, I could not locate any digital image of the copyright that was allowed.
*snort* Stampin' Up can go stamp itself. That's a ridiculous policy.
Good thing I never buy any of their stuff new, so I never had to agree to such dumb rules. While I don't sell cards I think it's silly that companies try to limit what you can do with their product beyond what's dictated by common sense. It's a tool. Can you imagine if wrenches or spatulas came with the stipulation you had to credit the manufacturing company on anything you made with them?
I don't worry about it a bit. Never did. If I buy a tool, which is what I consider stamps to be, I can use them in whatever way I please. Those policies aren't legally enforceable. If they want to come after me for the few - and I mean few - dollars I MIGHT make selling cards, bring it!