I don't think they expect anything in particular. It's just a sad fact that the transaction is asymmetric. It may take you a while to read, but it costs them ve

I don't think they expect anything in particular. It's just a sad fact that the transaction is asymmetric. It may take you a while to read, but it costs them very little to send you spam, and there is apparently a non-zero conversion rate. I guess from their point of view, they have no idea of your current position, whether you are going through a break-up and want to move cities, whether you hate your boss, or whether you're just bored. They are simply putting out offers and playing the percentage game.