Quote from ADP: '"Enter your email address to receive your private access-code via email"

 isn't that hard to fill out. Even not for an impatient Poser user hunting for free crap ;)'

Not difficult to fill out, but not desirable either.  When you know nothing about the site that prompt might as well read:

"Enter your email address so we can sell it to every [censored] site mailing list we can find, filling your email box with a boatload of crap mail every day, so much so that the address you give us becomes useless."

This is my point.  If you don't know sharecg and you have no idea what it's about, it is relegated to the status of yet another site that wants information they really don't need for you to perform a rather simple activity.

Which leads people to wonder why they would want it in the first place, and the most jumped to conclusion will be that they are selling the email addresses for spam.  Oh, and just to head off the eventual "But you could put up a thing promising you don't do that", funny thing is it's usually the sites that make such a big deal about not selling your email address that are the worst offenders.