I guess they could sell proper removable plastic films... They'd be pricey, but they'd do their dirty job!
I've read somewhere that there has been a slightly improvement about the reflections from the previous iPad, due to less distance between the screen layers. According to the source (anche the picture) iPhone is stil a lot better for that.
Sorry can't find the article
edit: look, these pictures have been taken before sundown, in outdoors: the iPad (2) has a protective film on the screen and there's no reflection on it