Until recently, credit card companies explicitly prohibited that. One of my biggest objections to the whole CC scheme, even though it worked to my advantage (cash and check payers effectively subsidize my CC benefits).
If I were the US mint I would give priority to collectors and require the bulk buyers to wait 1 week before placing orders for new items. I would also limit the production of commems to 50k or less.
How do you define a "Collector"? How many sets will you allow him to buy? Because I can pretty much guarantee you the dealers will get around the restrictions, and with a 50K limit you will probably find that a LARGER percentage of the mintage will wind up in the dealers hands with the collectors having to pay through the nose to get them. Of course the lucky so-called "Collectors" who just want to flip them that are lucky enough to get some (and they will be able to get around the restrictions as well) will love it. So what this will do is make it MUCH harder for the collector who just wants one for his collection to get one without paying a huge premium. My point earlier about the credit card was that people were lined up out the door at K-Mart to buy the sets at issue price, on time, at 18% interest, than have to pay $120 cash at the time of purchase.
I think the mint could do a lot better if they didn't need congress approval for any major decision they are faced with. When people bring up mintage limits, that decision was not up to them.
Edit - post was about re-opening the order window on the '13 silver eagle set to sell cancellations and returns. I haven't confirmed this so I will shut up.
That depends on the item. Commemoratives usually have their mintages set in the authorizing legislation. Mintages on the bullion coins, proof and mint sets, these special ASE sets etc are set by the mint officials not Congress.
I wish the mint would make some nice looking commemorative coins featuring designs with Liberty once again instead of these special interest group coins we seem to get every year. Though I also think the mint should have the authority on its own to issue commemoratives and not have to rely on Congress passing bills specifying which coins are minted when and at what limits. I also think the premiums on some items are a bit too high overall. I know the mint is run as a business and with the intention to make and not lose tax payer money but sometimes the premiums seem excessive to me. I'd also like the mint to sell standard non proof bullion ASE and AGE's so I could just order from the mint direct and not have to go through other vendors. I also think it would be a good idea for the mint to hold a certain number of limited mintage sets in reserve to allow people the chance to return a set if they get one with some product defects. Selling them all out and then not offering a replacement for people that may get stuck with non pristine set seems a bit harsh even if they will refund your purchase price.