Just because it is standard doesn't mean it is acceptable.
Therefore there will always be a tiny chance left for one party to get bitten in the ass down the line. The company has to decide if its them or you that is exposed to that slight risk.
Good luck finding a company that picks them rather than you.
Rereading, I realise that I haven't been entirely clear. I hope you get the idea. IANAL.
If service providers didn't secure a license from the uploader/creator of a work, this could happen:
- Jim McJones uploads his photo to flickr
- flickr displays his image to the public
- Jim McJones sends flickr a cease and desist or sues for copyright infringement
Which leads to... huh? Obviously the intent when you upload a photo to flickr is to have them display it for you. But they need a license, and since this is a legal issue, it needs to be written in a legally specific way. Thus, that's what everyone has done.DropBox's clause relating to this was already decent and fair in my opinion. Of course, I am not a lawyer or legal expert, just someone who both creates content and runs websites which distribute other peoples' works.