I'm not so sure it's related to his being famous, but rather that he was a Britain. Thus, the extreme interest in him from the British Isles.
I am not from the British Isles but find Carausius a very interesting subject. His coins include some very interesting types and a lot of junk. He has some well made coins and things that are hard to tell from the barbarous copies. He has mintmarked coins and other mints that did not bother to mark the coins. We know enough about the history of his period to make things interesting without having the entire thing spelled out in complete detail. If so many dealers did not believe that any garbage that can be attributed to him is worth huge prices, I could see making him a sub-specialty.
You mistake me. I too have interest in his coinage. His and Allectus'. But, imho, because he was a Brit, Brits are willing to pay extra for his coins. Even his junk goes for too much on most occasions.
I suppose it upsets the non ancient people but we do tend to repost the same coins too often. I'll show here my second favorite Carausius which I showed here in January when it arrived as a new purchase. As an excuse I'll show my NP Victorinus from Baltimore which I bought to accompany the Carausius. The Carausius has a PAX AVG reverse but is garbled from being overstruck on a Victorinus with SALVS AVG reverse. Victorinus has more than one pose for Salus and, until Baltimore, I did not have the one facing right holding the snake. I like overstrikes and believe it is good to have an example of the undertype for comparison. Of course they were not the same reverse die (that would require way too much luck to find; these were made from hundreds if not thousands of dies).
Wondefull stuff, Doug. My Victorinus is on its way, nothing special like an overstrike but decent, for me.