Its not super crazy. When you consider the number of homes that have home gyms, or pools, or basketball hoops, trampolines, or swing sets etc. that people have, its a large number of homes. And even for those who don't, most houses in America are built such that one could buy one if they want.

I grew up in suburban Indiana, and when I went home to visit my parents, I counted it up and literally over 1/3rd of the houses I could see from their front porch had a basketball hoop in the driveway.