Memory usage arm vs x86

Off on a tangent on this one, but has anyone else noticed that the arm cpu based units use much less memory? My real world example is a comparison of a 50e (arm) and 80d (intel atom x86) with close to same config, same load, both have 2gb ram, the 80d can be using up 75% where the 50e is usually 40% or about. Just get a feeling that the arm code must be better at memory usage.