Mint sauce?

What do you make of these new designs for our coinage? A sort of monetary jigsaw puzzle. Quite clever (indeed one is tempted to say just a little too clever-clever) but my question is - why? Coins are essentially utilitarian items - it's what you can buy with them that's important, not how pretty or interesting they look. I imagine that what's behind it is the money to be made from potential sales of commemorative sets - but I hope we're not going to go the same way as postage stamps, with regular changes designed to do no more than make money.