I actually think price matching is shitty. It limits competition, i like the idea of trying to outdo a rival company, if everywhere matched everywhere, it'd be fairly pointless anyone doing a great deal, as everywhere else would do it also
I mean... It isn't really limiting competition, because the various services having the sales aren't colluding to set a fixed price. It's actually a form of competition, as one service competes to maintain parity with another in the price of the product, and as was mentioned, requires buying decisions to be based on quality of service.
To be fair, in digital game distribution, there's a limit to the amount of price competition that can even occur, as prices need to be cleared (and are usually set) by the publisher of the game rather than the retailer. Or at least that's my understanding.