That kinda used to make sense before e-commerce. Like you went into a specific store trying to find something cheaper, realized it was a bit more expensive than you expected and then tried to haggle for a price match. You could totally go back to the previous place and buy there but it would net you an additional trip. Stores would sometimes agree to reasonable offers as well so they didn't lose a sale. Online though it makes no sense. You're just half a dozen clicks away from buying it with someone else. If you're price matching it means you're full of shit.