A bunch of reasons actually. There are loads of places in the US where it's reasonable and legal-ish to go 80 mph. If you want a nice, affordable car that can g

A bunch of reasons actually. There are loads of places in the US where it's reasonable and legal-ish to go 80 mph. If you want a nice, affordable car that can go 80 mph without feeling like its about to fall apart, it will probably be able to go 120 mph too. There are scenarios where I would want a lot of acceleration or top speed (or both), legal consequences be damned. You're not buying a car that goes 120mph all the time, you're buying a car that can do that once if you need it to, even though you very likely will never need it. But most importantly, because people want it and companies are willing to build it.