Introducing The Fat Cage

I don't remember why, but at lunchtime I was walking down some stairs and I was wondering how fat people managed to do that. Not mildly plump people, but the real big fatties. I normally find that I need to look down to watch my feet and make sure that they are destined to hit the next stair. If I was really fat, my belly would obscure this view and I might misplace a foot leading to disaster.

I thought of two possible answers to this dilemma:
1. Fat people don't mind if they accidentally fall over, even down stairs, because they bounce and hence avoid harm.
2. Fat people don't use stairs (this is why they are fat).

So I think that solves it. When we discussed this in the office later, a friend mentioned an invention he'd thought of - The Fat Cage. What this would do is restrict access to certain things for fat people whilst providing minimal hindrance to those of a more moderate size. The sorts of things you might wish to restrict access to include (but are not limited to): nightclubs, nice restaurants, pies, fertility clinics and rollercoasters.

It works by erecting a set of vertical bars (like a cage) between where the fat people are and where you don't want them to be. They would be spaced close enough together so that anyone of a certain size would not be able to pass through without a serious diet, whilst anyone else could just get through without any real hassle. They could be used in conjunction with a doorway for restricting access to rooms or corridors, or in an actual cage-like formation for restricting access to cake bushes or doughnut trees.

It's hard to see a bad point and this invention. The only strange thing is why it does not seem to exist already!