That's fine for hardware and tangible products, but hotels and airfare are usually something you need to take advantage up in the moment (after watching prices for a while). Even flash sales function similarly I guess. If I know I want to buy something, then I spend the next few weeks scouting prices and looking for the deal. When someone shows the deal, I jump on it.
I'll have to check out Inivisible Hand! I've never heard of it.