Im maintaining a site I didnt build thats for car insurance. In the banner of every page is an input that takes you to a page with a form to fill out. I cant understand why an input is used instead of a link, is there ever a valid and semantic reason for doing this?
Occasionally, people have done this because they want a link that "looks like a button". However, it is bad design.
It was never a good idea, but in the old days there was at least some justification for it: it gave a button feel and functionality to the link. However, with modern web design there is no need to do this: the same functionality can be created simply by styling a normal link appropriately.
On the other hand, this is probably more of a style issue than a real problem. It may not be worth changing it if you are maintaining an existing site.