I mean seriously...if they had a problem with people having privacy then they should ban all Curtains to all houses/homes.
No need, they just scan through the walls anyway.
True but that doesn't exactly show what a person is doing behind said walls/windows/etc.
Would that work on a thick concrete wall?
Not exactly high definition but this article from 2011 shows some pictures using a "new" scanner through 4-inch and 8-inch concrete walls