In reply to miho:
Mike - good point but quite different circumstances once you think about it a bit.
If you'll indulge me (and Douglas will forgive the hijack):
For events, I'll very often sell personal use rights to the client. Most of my wedding clients get high res jpgs of their day (some still just want prints and books which is fine) and at sports events, I'll sell the same license, personal use, no publication etc.
The image in these circumstances is of principal value only to the client who commissioned them, not a wider audience so I'm not worried about them passing it on. I don't ever sell copyright though, I just sell a license to use the image.
For 'art' images (e.g. landscapes etc) it's a different game. Because the image is of potential value to other people as well, I'm reluctant to throw away potential revenue by enabling people to share such photos without my being rewarded in some way for the effort and investment I've put in to create it.
Always good to hear the customer view, but this one (often unspoken but not uncommon) professional view.