<wisper>I just order from the UK</wisper>
I have my vision checked in the contact store itself (for free) if I need it and then a proper eye exam during my annual physical check up (which is fully subsidized by my employer - a common practice, albeit at varying levels of support).
Believe it or not, it used to be illegal (in certain US states) to purchase reading glasses 'over the counter'.
That's right, reading glasses were by prescription only.