Aaactually, if you don't have a fancy digital balance, it makes perfect sense to have a system that deals in easily judged 1/2s, 1/4s, 1/16s etc. You can't work out 0.0625 by looking at it, can you.

Ok in the space age you might need to do things in decimals. But for everyday life a decent fraction is all you need.*

(though I have to admit, how anyone worked out their change before 1971 is a mystery to me).

*Handy when doing drawing too, comparing different things.