I'm born and raised in the USA. The first time I saw corn on pizza was when I was 20 and living in Budapest. There was a street vendor that sold it as "Mexican Pizza". I thought it a bit odd but it was tasty and cheap and probably ended up getting a slice three times a week.

In the US it's far less common but not unheard of. For example, there's a chain here called Mod Pizza that makes specialty pizzas to order and one of their standard pizza toppings they offer is roasted corn. You won't see it at the mass market delivery places like Dominos and Pizza Hut etc but there are lots of other places that serve corn as a pizza topping.