Used car seat/stroller

Is it weird/gross to buy a used car seat and stroller? Someone on my local online garage sale is selling it and it doesn't expire until my baby is 15 months. It looks like it comes from a clean home.  I've agreed to buy it because I feel guilty for registering for something that expensive. I know, I'm weird. I'm just so independent that I think, "I'll just get it". I know that's what showers are for I just feel like, well, if I can get this then I can register for other things.