I wonder about the Western stuff. At least in the US, it isn't terribly popular anymore. And the Victorian collectors (again at least in the US) got the green car in the FAO set, so they wouldn't need to buy it separately. The Add-ons aren't in the main categories, and there's hardly any content for the search to search that it's hard to find add-ons unless you already know they exist. If you search "victorian" on the US site, NOTHING comes out. Who, but a collector, would search for an advertising column or a "Group of Outlaws"?
They need set descriptions or metadata because search cannot operate without content.