we take our dogs every once in a while, I wish I could afford to take them more often, but with two dogs that's just too much money. They are so tired that you don't need to take them everyday. We had some work being done in the house over the summer and my landlord paid to put them up each day and they were so tired every night they went into their crates each night early and never made a peep.
I don't really think you need to put dogs in it, but I think its a fun thing for them to do once in a while. Especially in the winter when you can't take them to the park.
btw: many day cares offer seperate rooms for large and small dogs, we like that because our little girl gets scared around big dogs.