Yes, PVC plastic seat covers are cheap and look great but car manufacturers know about their toxicity out gassing cause to human health and don't want to be sued from car buyers. US would not approve it and that's why it's widely use in outside the states.

Read this article before making decision buying PVC products.

PVC plastic products outgas poisons

PVC products stink because they contain volatile organic compounds (VOCs). These are poisonous carbon-containing chemicals that are volatile enough to evaporate at room temperature. This process, called outgassing, is also a problem with building products such as plywood, particleboard, carpet and pads, paints, stains and glues.

Outgassing odours are most noticeable when products are new, but diminish over time until they finally disappear. A shower curtain can outgas for a month or longer, for example, depending on conditions. High temperature and humidity will speed up the release of VOCs.

VOCs can be toxic. Most commonly they irritate eyes, noses and throats, causing coughing, headaches, dizziness and nausea. The symptoms go away when outgassing ceases.