The costs are also very difficult to determine, where $1 sounds a bit high to me. Lets try to do some random estimates for a random game: 30% of the users wont touch the game whatsoever, and will just have it on their "list". Of the buyers, 0.5% will require some sort of support effort in relation , where 65% are handled by the auto-response and 30% by the first email by an employe.

Say a total of 5,000 downloads are from this "free" coupon for any specific game title. Would $500 or $5000 sound closers to the actually hosting/support cost that the publisher has.