Crediting a sprite sheet with no credit "license"

[Vipershark]

I've honestly never understood the existence of the permission thing for any sheets that weren't customs. I can understand rippers wanting credit and I fully support that but they can't realistically disallow someone from using those rips without permission.
If you're REHOSTING the sheet without permission that's one thing, but needing permission to use the rips in comics/games/videos seems ridiculous to me.

Obviously if the sheet is custom then you should definitely get permission from the person who made those sprites before you use them, but how can someone who merely ripped them and sheeted them tell you not to use them?