I think it's brilliant the same way that an evil genius is brilliant. Still evil though. And yes, that is actually what Venmo does if you try to type in "electricity bill"
Maybe they’ve updated it since I last used it, but I suspect that “dollar dollar bill” is still a subtle tag that indicates that the transaction was a “bill” payment.
I just checked and I still get four emoji: lightning bolt, plug, lightbulb, money with wings (those probably aren’t their proper names, I’m just guessing) with the text “electricbill”