Spam and most blackhat businesses are just that, business. The operators are your average greedy bastards, the great majority of whom are technically incapable twenty something men who think "the internet" is still in a dotcom boom. I'm not pulling this out of thin air, all you have to do is lurk in spam boards to see the prevailing mythology; a huge majority of 20-something spammers who want to live the Hip Hop lifestyle and who will do anything for money.
They themselves get scammed left and right by everyone from competent systems programmers who sell them backdoored tools to sophisticated mafiosi who open fly-by-night "online banks" to fake advertising networks that lure them into distributing their spam links and malware and then fold just when it's time to pay up, not to mention the ponzi schemes.
The life of a spammer is a bitch. If you were dealing drugs you at least have your tangible goods in hand and cash proceeds in the other. Spamming is like drug dealing, except someone keeps your stash and drop-ships it, and another keeps your cash and gives you a metered ATM card, nickle and diming you in every step of the way.
So the question becomes, what sort of spammer is making the real money (or the most of it) instead of asking if all spammers are making moolah. And the answer would be, the guys getting paid are not exactly in the spamming business :-)
People "down on their luck" might buy more dubious crap. Businesses in more desperate times might use less "palatable" marketing than they normally would.