Just thought I'd throw my two cents in about a potential resale marketplace, as such a system does exist.
I try every year for tickets to a non-festival event which, albeit on a smaller scale, is still pretty big and leads to a bit of a Glastonbury style "refresh and pray" ticket scramble when they come out. The event offers a marketplace where, if you can no longer go, you can sell on your ticket for no more than about 10-15% profit (and a little bit of your "profit" gets sucked up by fees I think.) On top of that the buyer has to pay an admin fee for name change of about a fiver if they sell it on within two weeks of buying their ticket, then £10 if it's been 3 weeks, £15 if it's been a month etc. etc.
If you want to sell on to a friend, you can opt for your ticket not to be listed to the public on the marketplace and just upload your ticket and send them a private link to access it and complete the transaction. You have to verify you want to sell to that person if they request access. In fairness, I can see the argument for not allowing trades between friends here - I could quite easily whack my ticket on Glasto Chat and promise to only give you access if you bought the ticket AND then transferred me another £X to my bank account, and I know with this particular event I'm talking about that this is something that has happened before. If you're caught bending the rules of it, the owners of the event have the power to ban you from their's and any similar events (there's a co-operative scheme in place because a couple of events use the marketplace concurrently), though how strictly this is enforced I'm not sure.
Hope that all makes sense! The system works well, cuts out the margin for touting (OK you can make a couple of quid profit but given that I paid about £90 for my ticket to this particular event this year I'm not sure you'd see people going through the stress of buying tickets they don't need on ticket day for an extra tenner) and ensures that pretty much every ticket which is sold goes to a good home - I think the marketplace closes maybe a week before the event. I don't see why Glastonbury couldn't operate that. I'm sure demand would still completely outstrip supply and not everyone would get a ticket on the hypothetical marketplace, but it seems like a lot less messing round than having a pagechecker or what have you.