S'mon said:
I believe Sir Walter Raleigh was granted a patent (monopoly) on all beer sales in London. If you wanted cheaper than Raleigh's-sale-price beer, you bought it illegally.
This can be explained in the following way:
A thirsty patron justs wants a beer. She doesn't care if it's Raleigh's or Fred's, but she does care if it is legal or illegal - because if illegal, she runs the danger of prosecution.
Therefore, if she buys an illegal beer she will want a discount for running the risk of prosecution. Therefore, Fred, if he is to sell any beer, will have to sell at a discount (to put it another way - he will have to pay a premium to his patron ie give more beer for a given amount of money).
S'mon said:
If you were a brewer and wanted to get more for your beer than Raleigh's-buy-price, you sold it illegally.
This can be explained in the following way:
A brewer justs wants to sell his beer. He doesn't care if the purchaser is Raleigh or Fred, but he does care if the sale is legal or illegal - because if illegal, he runs the danger of prosecution.
Therefore, he will want a premium for running the risk of prosecution. Therefore, Fred, if he is to acequire any beer from a brewer, will have to purchase at a premium ie more expensively.
Thus, the illegal beer vendor pays more for beer, and sells for less.
Thornir Alekeg said:
I say it is unlikely that there would be much of a black market that would pay more and sell for less than the existing market, if doing so was illegal. The profit margin is lower and the risk is higher.
You are asking, in effect, why would Fred engage in the trade described above? Maybe it's the best work he can get. Unlike Raleigh, he may not have the opportunity to go into a business that will deliver monopoly profits.
Thornir Alekeg said:
Well, I haven't had a lot of experience fencing things, but IRL, stolen items are sold for less money than market value, but I believe you will also find that it pays a lot less than the market would as well. The reason someone who steals an item is willing to sell it to a fence or pawn shop for 20, 30 or 50% of its value is because it is stolen. The restriction I keep talking about is that the person could be arrested for trying to sell it through legal channels.
That is, the thief pays a premium (by granting a discount to the pawn shop) in order to avoid scrutiny.
Notice the difference from the beer example above. The customer for beer has nothing to gain by buying black-market beer, but takes a risk - thus the discount to the thirsty patron. The thief has everything to gain from offloading to the pawn shop, and it is the pawn broker who is running a risk - thus the premium incurred by the thief (ie the discount enjoyed by the pawn broker).
In the case of black market magic items, who is running the risk in the black-market transaction - the PCs vending, or the organised criminals purchasing? Assuming that the PCs could, if they like, sell legally to the monopoly - assuming, that is, that the restriction is not on the PCs selling of items, but is on the criminals' acquisition of them for resale (because, ex hypothesi, someone else has been granted a monopoly on the item trade) - then it is the PCs who take the risk by supplying the criminals - hence, they should be paid a premium (that is to say, be granted a discount on the gold they purchase with their magic items ie get more gold for a given magic item).
Thornir Alekeg said:
In this case it sounds like there is no reason why a person would fear selling the magic items legally, they just want more money for it.
Correct. And to get more money, they have to run a risk, namely, of being arrested for selling to an unlawful trader.
Again, what motivates that trader? Presumably, like Fred the brewer, it is the best gig that he or she can get.