Buying Some New Frames

I'm a chick who loves glasses. Daria was my idol growing up so I've always considered them to be pretty cool, even though haters away tell me I look better without them (like it's some kind of a compliment or something). I love men in plastic frames, and I love men who seem like they might be frequent visitors of, so I'm down with eyewear. 
Coming to Paris was actually a really nice change because this city seems to be huge on them. Every block I'm on there's at least one shop, and they always have the chicest Tom Ford's. So when I was in the market to get a new pair to add to my collection I popped into a shop on Rambuteau (my favorite street) and picked out a few pairs. But I was a little confused about how to go about buying them because I hadn't brought a copy of my prescription with me, and when I went into the store I didn't see an optician (in America there's always a doctor right next door), but I was surprised to find out that actually when you buy some eyewear the store will give you an exam free. It's not like visiting the doctor at home where you have to do all of those fancy eye tests, but it gets the job done. The more you know I guess.