First of all, they tore Tiger Stadium down which probably was there longer than any of those bars along Michigan Avenue. So tearing the blocks down between Trumbull and downtown wouldn't have made any difference. They had to tear buildings down to build Comerica too so it's either one area or the other.

As far as the vacant lots that surround the stadium the same thing could be said for many areas around Comerica Park. Out of all the times I've been in Detroit nothing has ever been built on these lots nor have I seen anything other than a new arena for the RedWings planned to be built on any of those lots. Look at the area to the north of the Fox Theater on the other side of the expressway, it has numerous blocks that are just concrete or dirt lots, same as in the area around the old Tiger Stadium so really it's the same thing just in a different location.