I thought about Detroit as well. Actually, we really need one north or west of Detroit. The south is pretty well covered, and that's not including the World Famous Detroiter. <blech>
Something north or west of Detroit would be great. I think the problem is the cost of the land and the taxes. That area has gone crazy in the last 20 or so years.
Using beepers to alert waiting drivers that a shower is available would be great, and if there were a way to get a massage, even just neck & shoulders, (oh yeah - & JoeBob's feet, too, he's weird that way), it would be wonderful. And don't forget the trees!