Am I being a snob? In laws bought used car seat

My father-in-law bought a 7 year old car seat and stroller at a rummage sale and gave it to me as a baby shower gift. It is not in bad shape but can tell it is old. There is not padding on the car seat. Just plastic and cloth cover. Plus, he didn't know the people he bought it from. I mean, 7 years, how can you garrentee it has never been in a accident or that it is up to safety standards. Am I being a ungrateful snob? I would rather buy a new one that has instructions.