In the Rest of the World you do have some cats kept indoors the whole time but it is not the normal thing to do. Only in America are they de-clawed, kept inside an apartment for their whole life and not given special 'cat' rights to do things like climbing really 'dangerous' cat ladders.
Cats very much have their own patch to patrol. Their home is there for them come feeding time. Despite being portrayed as antisocial they do interact with other cats in occupying this larger territory.
In a society where people let their cats patrol their territory it seems cruel keeping them indoors. In a street with lots of cats you would let yours out too. But if all the cats are locked away and not able to roam then you would lock your cat away too.
Interesting how Switzerland also has much more cat friendly traffic than what you get in America. Maybe this is why America has become this place where people lock up cats and daren't let them roam freely.