I'm with Dunheved - this is a fun nod at the anachronisms present in the shire in Tolkien's source material, relative to the rest of the setting. It is clear from The Shire book that these are weird curiosities in the Mathom House, not something that's in use. It's easily ignored if people don't like it as these are explicitly weird items in a museum. The text certainly doesn't have hobbits riding around in them.
Cross-bows: show up in The Nature of Middle Earth as used in Numenor, for those looking to bring them in to the game and wanted a source direct from the author. But understand some of you are veterans of the topic and don't need to go over it, but thought's I'd offer it here as there are some it will be news to.
The Shire has umbrellas, golf, waistcoats, clocks and matches. It even has a reference to a pop-gun when Gandalf speak to Bilbo. The Dwarves have clarinets!
"The Shire "is in fact more or less a Warwickshire village of about the period of the Diamond Jubilee" [1897] -
http://tolkiengateway.net/wiki/Letter_178
I thought the idea was "if it's not in JRR Tolkien's writing, it is not in the game".
This seems quite restrictive: the Woodmen are a great example of building out a culture where we've got very little in the original text, but The One Ring makes them fit naturally in to the source material by building on what little we have and using the work of William Morris, who inspired Tolkien. The One Ring does a great job of this kind of thing, in contrast to MERP (for example).