You can share content via email too. It's not just for new social media sites.

(I'm actually not sure if this makes your SPAM analogy more or less appropriate.)

what I don't like about the explosion of share menus us that email has been subordinated to the share menu. I may be a constituency of one, but email is the only way I share. So instead of tapping or clicking "email", I have to tap "share" then email.