Tipping is something that I'd like to see whales doing.
We don't have yet Steem dollars, but when we do, I'll probably start to tip good writers every now and then. We really should have a tipping button when dollars start to flow into system!
I might even give some Steem Power for new users who are exceptionally good writers but can't afford to buy it themselves. It's good way to incentivize them to use Steem more often.
Tipping feature would be nice, but if someone has a whale-sized stake, then an upvote is a pretty good tip.