Nice logic, well done!
But what would you say, if a person has requested an exclusive theme for himself, and he wouldn't like somebody else to has this theme besides the requester? And the creator of a theme, of course, won't going to sell it to anybody else: you offer him 500k, 1kk, 2kk etc., but still, he is persistent as for this question. And you, who got used to get anything easily, are offended that somebody doesn't want to satisfy your whims. And you go to a site, or to a coder, and tell there: "These fuckers don't sell themes to me, help me with stealing them then!". And you pay real money to get a stealer.
As for your another phrase about "expensive" themes, there's only one answer - the market's rules work here well. If nobody would buy themes for 1 and more millions, nobody would sell it. But people are interested in it, you can't deny this fact. You wouldn't have any doubts to buy an original theme for 1 million if you had this money.
I want to say, if you don't want to pay so much - don't buy themes these themes then, there's a big assortment of midi themes for low prices. If you don't want to respect other people's spent time on really quality themes, why does anybody should respect your useless opinion?