Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

What's an economic explanation for why greeting cards are so expensive? 
As one answer points out, people buying greeting cards care little about whether they cost 25 cents or $5.  Those are both small amounts of money and it's not something you buy often---also people feel the need to spend money because it's a gift. On the supplier side, it should be noted that the cost of cards has little to do with the paper they are printed on.  There is an expectation that cards are new and unique...something the buyer and recipient have never seen.  So they have writers and graphic designers constantly cranking out a large variety of cards and replacing existing cards with new ones, of which only a small number get sold before they move to the next model.  Relatively speaking, there is a lot of human effort per thousand cards sold.  Then of course there is the real estate they occupy in the store (disproportionate to a bunch of pieces of paper) and other retail, marketing, and distribution costs.  I'm not saying margins are particularly thin, but if they were crazy high we probably would see more entry as you suggest.