Quicksand

I was watching an archaeology program on Sunday night, and it got me thinking about quicksand. When I was a kid, you couldn't watch TV for more than 10 minutes without seeing some poor sod encountering some quicksand and being sucked down into it. Sometimes they'd escape, or be rescued, but sometimes they'd meet their end there, especially if they were the bad guys.

I even have vague memories of being around beaches when I was young and seeing signs warning of possible nearby quicksand. Just scaremongering, or a real hazard?

In recent years, I don't remember a single TV programme or film that has had any quicksand in it. Not even 24's Kim Bauer (a girl who has managed to get into pretty much every scrape imaginable) has managed to encounter this particular hazard. Where has all the quicksand gone?

I have some theories:
1. Quicksand is not real, and I in fact had no real childhood - I have imagined everything up to the age of 12, and some of it is inaccurate. Or maybe I have been given false memories by a therapist and/or evil hypnotist.
2. All the world's quicksand has been gathered up by terrorists for use in some new, ultra secret WOMD. One day soon, London will wake up to find all the streets have been coated in two metres of quicksand and everyone will be sucked down to an early grave.
3. Quicksand has become too cliched and film-makers have tired of it.
4. Over the last 20 years or so, humans have evolved special feet that let us walk unaided over quicksand (and possibly sucky mud too), so even though there is still as much if it as ever, we just don't notice it any more.
5. I'm not watching as much TV as I did as a kid.

If anyone does know where and why it's all gone, then answers on a postcard to the usual address.

Here is some information I found on the interweb about quicksand. It doesn't really answer my question though.