Appics can now add value to their own token and build a community around it. Just like STEEM it will be a tradable token so it will get a certain worth on the market.

If they used STEEM they would be stuck with the same people trending as on steemit.com (is 1 reason). They also need to acquire (if not delegated) a big stake to have influence on their own app (is another reason).

I can think of a few more (might make a good vlog topic).