Why do my rear pads wear quicker than my front even though i brake more with the front brake?

I asked this question in an LBS and was told “mountain bikers use the rear brake more”.

I’m not convinced as I tend to use the front more.

Perhaps more crud is thrown on to the rear disc?

You probably drag the rear more down steep stuff, I imagine.

Fronts’ do all the work, whereas rears are just for steadying/skiding – therefore they are more likely to work at their operating temperature?

I replaced both sets last week – fronts’ had been in for a year vs three sets in the rear.

Does that also mean that fronts get bedded in better also?

Perhaps more crud is thrown on to the rear disc?

That’s what I’ve decided, when I ride through a muddy puddle it’s always the rear that rubs for a short while due to the grit/crap thrown at it from the front wheel.

What BR said would be my guess