That point from @fisher.felix about the grooves being just for design is interesting, but maybe it's not that weird. Look at the cave paintings in France, those weren't for use either. It seems like for early people, making a tool useful and making it look a certain way weren't separate jobs. Decorating a spear thrower or carving a pattern might have been part of making it right, not extra work. So maybe that urge isn't about taking extra time for no reason, but about the reason being different than we think. It changes how we picture their whole day.

Oh totally, I started tracking my craft supplies the same way and it really makes you think twice before buying more.