Whilst in the waiting lounge at Dover Cruise Terminal I came across a large displaystand on which were placed back copies of moroting/Gardening/Ladies/ Magazines and the prvious months Readers Digest- all for free .
Some magazine publishers and most newspaper publishers sell large quantities of stock to airports and such like for a nominal fee. These are then given away to passengers, etc, and it's used to reasonably cheaply boost circulation figures for advertising purposes.
I can see now it gets the circulation figures up quite painlessly. Another mag that I have a gift subscripion to [The Oldie]will from time to time invite readers to submit 10 names to recieve a complimentary copy, more circulation pushing I guess with the odd chance of another subscriber.