I use those scrubby mats inside and outside the shop doors, and outside the garage back door, and the house door. I keep a scrusher (that might be a brand name, but its one of those boot cleaners inside the door to my shop, and outside the door to the house.
The theory is that I clean my shoes on the way out of the shop and wipe my feet at each door. I walk across some gravel and then lawn and then concrete on the way to the house and wipe my feet up to 5 times on the way in, depending on what I've been doing in the shop.
I also am pretty on top of metal on the floor with one of the magnetic sweepers. My kids know that if they remember to wear their safety glasses, gloves, and good shoes and knock when they come to the shop, they can earn a bit of money if they run the sweeper around, which they already seem to think is great fun. So I don't have much metal on the floor to begin with.
However, I also work with wood and plastic, and they aren't nearly as thrilled about running a broom, so that's why all the sole/shoe scrubbers.
If I ran into problems marring the floor, I'd probably start looking at the next level of cleaning. Thankfully, however, it wouldn't ever be an issue of harmonious household. My wife and family watched (and helped a very little bit) me cut, mill, sand, tongue and groove them on a normal router which is a huge pita, resin seal, sand, resin seal some more, sand some more, and finally, install the hardwood floor, so if I happen to mar it... oh well.