Size 0 clothes

The petition is entitled stop Asda stocking American size 0 (size 4 UK) clothes for teenagers and women and the explanatory notes read

"Asda are going to stock size 0 clothes (equivalent of age 7) for teenagers and women. These have a miniscule 22" waist. This is very irresponsible and could cause anorexia or promote it or help anorexic women stay that way. It should not be allowed for size 0 clothes to be stocked!"

I have a couple of issues with this:

1. Size 0 is American. It's UK size 4. Why use the American size? Oh yes - that's right - the shock factor. Clever. Not.
2. There are, in fact, some teenagers and adults who are naturally very small. They are few and far between, but as a woman who is quite naturally outside the normal ranges in a different respect, I am not in favour of legislating against rare things that make shopping easier for the unusually-sized or -shaped!
3. I'm damned sure Asda's not alone in this sort of stock choice. Why single them out?