Those are 3 awesome reasons! Hope more people will realize them soon! :)
A friend of mine has been unofficially promoting and helping out newbies on Instagram and the tag #steemit there. He also issued a warning against a weird behaving account by the name "@steemit" who had insisted it was an official account and when asked to prove it, he had replied on Instagram instead of here on Steemit. Hope users aren't exposing their keys to other accounts on Instagam.
thanks for sharing, checking it out now! I have yet to promote steemit to my Instagram followers :)