I imagine it is illegal (someone else already said that here). Law and morality are not the same thing and are fairly often at odds. Historically in the US, slavery was legal at one time in some states. After it was abolished, racism was embodied in the legal code. Plenty of morally high minded people disagreed with those laws.
Whether legal or not, I don't find it acceptable. Similarly, on CF lists, people routinely post announcements that they have leftover medical supplies of some sort and are willing to give it away for free (sometimes on the condition that the recipient cover postage, sometimes not). This is generally viewed as socially acceptable on most CF lists because medical expenses for CF are extremely high and people coping with CF are typically financially devastated by that fact. On the only CF list I own, I announced that this was not an acceptable practice because I think the price of exposure to the germs of another person with CF outweighs the value of the supplies. So I think that's Not Cool either, even in cases where it happens to be legal (and legality of it varies by jurisdiction in this case and probably also depends on exactly what is being offered).