Paul, thanks for stopping by and commenting. Please, keep in mind this is more of an amusement park than a real RR station. There is a rideable miniature train that circles the park and a few rides, as well.
The actual town of Maricopa has a train station that is serviced by Amtrak. The station isn't near as photogenic as this one.
That makes more sense. I thought to ask which line such a small building could be involved, given the older design but new warning stickers.