Free is free, and that's it.
I remember there was an issue with department stores that were consistently offering their jewelry at 40-60% off. As they were never even offered for sale at the full price, they had to add on some disclosure to that effect. What if that would apply to all these publications? They could say" we think these paper is worth at least $1, but you may not agree. So we're giving it to you free. Please take it, so that our circulation figures have some real people on the receiving end." Now that would be honest! In truth, it is advertising rather than subsciptions that bring in the profits for publications.