Okay. To me that means buy it if you want it, but don't come crying to me if you don't purchase it when it's available and then complain when it's sold out. The fact that it will someday go oop isn't an issue - that's a fact of life, whether from Mosaic or any ol' record company.
Personally I don't know anyone who does buy Mosaics only to resell at a profit at a later date. As others have mentioned, there are better ways to make money. That said, I'd be lying if I didn't tell you that I've bought sets off the "endangered" list knowing that, if I didn't like, I could always sell it and recoup my investment. It's better than buying new CDs and have them depreciate upon opening. Besides, it's good for Mosaic in that they sell out and maximize their profits.
I suppose you mean in regards Ebay auctions. It's very true that the buyer is the one setting the selling price in an auction. So you suggest restraint? As in, I'm only gonna bid this high 'cause that's all it's worth to me. But if it's "worth more" to someone else why shouldn't the high bidder get it? In a fixed-price sale, if the asking price is "too high" then nobody is forcing the buyer to buy it. If the seller is serious about selling, he'll lower the price to market rates. Supply and demand and all that.
That's a completely different issue entirely. But if a Mosaic set goes oop, you might as well just burn a friend's copy instead of purchasing a ripped-off Euro version, right? The artist won't get any money from it either way and the dough you save can go back into Mosaic with another purchase.