Not up here in Massachusetts. They're all over the place. They linger on store shelves, because even here, where the Irish palate has pretty much ruined most food, they know enough not to use top-sliced buns, unless there's no other option. The side-sliced and top-sliced options get about equal shelf space, but when it's cook-out time, the side-sliced are the first to go, and it's a serious consideration of "do I just skip hot dogs, or do I buy top-sliced and have to spend the rest of the day apologizing and explaining that the store only had top-sliced" if side-sliced aren't available.