Because done right, you can actually reset the tire to a seal this very same way.
In artica and other northern regions (while there's ice), this is what they do when their tired pop out. They run tired under very low pressure for maximum grip but they have a tendency to pop off. So set them back in this way and repressurize them if they need to adjust.
Mouser has it exactly right. This was featured on Top Gear and another Jeremy Clarkson special, and I think one of them called it "The Icelandic trick". This seems to be popular among very, very cold places.