What I abhor most in the whole ebook discussion is not the drm as it but the fact that we pay for having a right to use a file that we don't "own". I even read on a website that if that vendor stopped existing you had to delete all the files you bought there

The actual drm is a good way to ensure this for average users.
Do you think this will stay the same if watermarking is used as a general rule ?
I hope I'm clear, sometimes I really struggle to explain myself in English.