So if you buy a used Honda that the salesman claimed had been "refurbished" and it turns out to have a bad battery then it's Honda's fault simply because it's a Honda car? In your world the manufacturer is always responsible no matter who does what to their products?
I've bought refurbished ThinkPads from IBM and Lenovo. They were all "like brand new and everything is packed nicely with plastic bags."(*) That yours wasn't further underscores the likelihood that it either wasn't refurbished by Lenovo or that someone had bought it, used it and returned it before you got it. Either way, how can this be Lenovo's fault?
(*) One exception was when the product description warned that there might be exterior "blemishes." There were a couple of small scratches on the LCD cover.