At our ryokan, we have beautiful tatami mats on the main floor, and in the dining areas. A wood or tile step before you enter the tatami room reminds guests to remove their slippers.
The tatami mat in dining room
While beautiful, tatami mats are expensive (one price quote was close to $1000 USD) and somewhat fragile, as well as hard to wash, although they are easy to vaccum or sweep. An errant pair of heels or careless movement of furniture can cause irreparable damage.
The cost and care required is easier to understand once one has viewed the process used to create these classic Japanese floor coverings. Tatami mat manufacture video.
They give a warm, restful glow to any room they grace, but are a bit firm under a futon.