Of course a share value can fall.  But it can't really fall while the company is still okay.  It represents ownership.

A coin on the other hand?  A coin can go to zero while the company is fine.  Why should the company care? 

The problem with a coin is that there's nothing to prevent the company from just plain walking away.  It got the ICO investors' money, it owes them nothing, so...  done deal, right?  It's over.  The company gets nothing for whatever resources it devotes to the ICO coin after that point, so sooner or later it's just going to cut expenses and drop it.

You're not going to get real investors investing in something that creates no obligation and confers no ownership.