I only started with pipe several years ago,
when I first started, Esoterica was fairly available,
I remember Tilbury and Dorchester being 2 of my early faves...
...but, I think at some point, due to the pipe boom I guess, demand outstripped supply and they've been playing catch-up ever since, the situation may have also been aggravated by the high dollar aftermarket - many people would buy the stuff because they knew they could flip it for a profit, and the big 2 always sell out in a manner of literal minutes - there may even be a few bad apples in the distro network who keep it to sell only on the aftermarket, who knows? But as of late, ebay has seemed to crack down on all that and Esoterica listings are only a fraction of what they were, maybe it'll help?
See also:
http://pipesmagazine.com/forums/topic/looking-for-krumble-kake
&
http://pipesmagazine.com/forums/topic/esoterica-tobacciana-a-history
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