Actually I find it's the opposite--people doing the math in their heads often find single-digit decimals easier to work with than fractions.
For example, when .8 mils is your dope for a 10 MPH wind, you estimate average windspeed at 6 MPH, that's a .5 Mil hold. Very easy. Very fast. If your dope is 2.75 MOA or 2 3/4 MOA, that times .6 = ....not something most want to try and do quickly in their heads.
If you're getting the answer spit out of a device for every shot, it doesn't matter as much.
