My understanding is that Adafruit harvests these buttons from Glowforge units lost over the last couple years of product development. Now that units have been shipped for mass destruction… er… final durability and other testing, the supply is great enough to make them affordable. These are your first step in creating your own competing laser cutter!
I s’pose you could use it for other stuff, too. Adafruit mentions some neat ideas about using them for user feedback in their video. Probably some of the same kind of ideas Glowforge is using, I’d guess. Anywho, I know there are at least a few people on here that like to do projects that might use this kind of thing.