I'm worried a bit about the privacy in zapping. I remember when wallets were still single-key and you could see how much people transacted and years later that data doesn't go away. To see somebody was moving around hundreds of BTC with the same wallet he just paid a coffee with ... can get dangerous.

So now we tally up zaps received (but not yet zaps sent) and in a not so far future, those top receivers will look like ultra rich.