I think what they shoot for is more site exposure, the product placement that will increase chance of a sale to those that sign up for the course, etc. They do profit, but they don't "take away" anything more from the consumer than the consumer is interested in providing. They might get loads more "gain" from the transaction, but it's not for much "cost" on the consumer side!
Not arguing really; your statements are correct. I just see this as one of those instances where both sides gain more than they "expend"!