It’s hard to mimagine some one woud build uncomfortable seats to begin with. When car companies try to add support, they run the risk of not making it adjustable enough for everyone. Having said that, buying a car with uncomfortable seats that cannot be easily adjusted to, is a big stretch for me. Though I tend to agree with @db4690, at at very least, OP should have at least, delayed buying a car until options like @MikeInNH has commented on can be examined. All dealers would be well served by suppling this information to respective customers. I agree about the shoes too. The best ones tend to fit well from the get go, and seats should too.