I originally discovered it as a feature of the HomePods. I’ve been using it with a sleep timer for a white noise generator for over a year (Ocean and rain are quite nice).
I’m guessing some people who don’t have HomePods, may use their phone (often beside their bed), in a similar way. Why is that weird?
Apple’s already bought the rights to this “unlimited” length/looping audio track; so now folks don’t have to pay for one of those apps like “Calm” or play a YouTube video all night from their computer or something for their white noise. Very cheap for them to implement. Big win for those who use it. Sounds like a win for me.