As someone who uses a 60% keyboard that is without numpad, F-keys or arrows I can say that it actually isn't really more useful for me. I'm actually looking to switch to a 40%. But I can wholly understand your surprise - I was surprised too and my first mechanical keyboard was a G80-3000 - a warship of a keyboard, only comparable to the Model M in size.
I think this video[0] is a great introduction why people who don't take their laptops around enjoy using tiny keyboards.