I would quite like it if the club introduced a system of "disloyalty points" for those STHs who don't actually use their tickets, or pass them on or sell them to someone who can. The club knows when a ticket is activated at the turnstile, so after every match they could deduct say 10 points from the accounts of STHs whose tickets weren't used for that match. This would have the double benefit of either reducing empty space at home matches, and/or making it easier for those of us who do go to every home match to get tickets for crucial away matches.