1. Not everyone can afford to.
2. A house in the suburbs? Bought with what?
3. People need to work ... at the same time that the parks are open ... and they're off when the parks are closed.
So, nearly anyone should be able to squeeze this workout SOMEWHERE in their day - it only needs some floor space and little time (should be less than 30 minutes) to do a decending set from 10 with 60 secs rest in between. However, the problem, as Noir has pointed out, is mindset and motivation. Most people will not put aside 30 minutes to do this because it's easier to veg out on the couch.
I haven't come across too many other exercises that require less equipment or time or complexity and still offer a fairly broad range of conditioning...
It's good to be an Old Bastard when you can have 40-something Hotties like the ones in that list. The only one who does nothing for me is Pam, and I think that's just because she's so "over-exposed". My older brother has had a thing for Michelle Pfeiffer for as long as I can remember and I can see why...