Having run a shop for collectors for about 30 years I think I have finally cracked this spotting business. I believe that ALL men are borderline autistic (Asbergers at least) and have an obsessive desire to complete patterns, be they train numbers in a book, badges in a series, pubs to visit, or even those whose motto is "so many women - so little time". As a button collector and former trainspotter I dont exclude myself, and I always have a little smile at those who come out with the same tired old anorak/thermos/egg sandwich jokes, because if you dig deeply enough their own autism will be manifesting itself in one way or another. It's true that woman don't seem to suffer much, although possibly their desire to own a separate pair of shoes and handbag for every day in the year may be a feminine version of the same syndrome.
By the way did you know there is a barbed wire museum somewhere in the US? I believe it has quite a lot of visitors.