(I agree totally, am just adding some things I think are important.) It also levels the playing field in other ways: imagine someone who has a slight tremor in their hand, and can't use a mouse as quickly as others. Many people have jobs (including relevant ones) or families that might require their attention during the critical minute-long window.
So, unless your goal is to have a conference filled to the brim with the world's most dextrous, carefree, and well-off people, "first come first serve" doesn't make any sense... it is "fair" for some definition of "fair", but it is using a criteria with existing fundamental biases. As another example: "auction off to the highest bidders" is also a fair allocation scheme, yet many would balk at that.
At least this year they pre-announced the tickets; last year the time zone advantages were more drastic, and the "I have other things in my life that require me to be on certain schedules" issue was more costly. You also run into human advantages, such as "do you have friends (or minions) who are also on crazy schedules and can alert you". People like myself even had programs (and/or services like Pingdom) watching for changes to the website (although at least that is in some way related to the concept for the conference ;P).
I'm still not sure about your idea...it just seems to boil down to reducing the incentives while keeping the price high, so of course there is some point where you can adjust that mixture to where you will only sell the number of tickets available.
I agree with the argument that the keynote attracts some people that otherwise don't care (though the WWDC is always super crowded post-keynote), but considering the other conferences that have this problem, the volume of people buying tickets, and the volume of people upset with the process that denied them tickets, I'm not convinced that going keynote-less would be sufficient to erase the issues with ticket buying. And that's really the only knob you have except for raising prices, which certainly does your attendee demographics no favors.
I also really have to agree with saurik that, even if you can reduce demand to have tickets sell out in, say, an hour, simple distractions that morning (kids, forgotten meetings, car problems) still mean you miss it, which will again heavily skew your demographics to the set of people glued to twitter who would never have missed the 30-minute, 15-minute, and 5-minute warnings of impending ticket sales. Some of those people are going to indeed be the true fans, but many will just be seeing those by virtue of attributes that bring no advantage to the conference, and may limit its reach. It takes all types :)
JSConf also sells out in like 10 minutes, which is why they moved to a lottery system. There are no media events or giveaways there (mostly), just a really really good event that refuses to get larger because getting larger may (probably will) spoil some aspects of the event that make it really good.
Think about the lottery this way: if WWDC sold out in two minutes, it's likely that more than the number of people that can attend were on there trying to buy tickets at the same time, so it was really down to a lottery of timeouts, latencies, and overwhelmed systems. A real lottery at least makes it slightly more civilized, doesn't give geographic or equipment-based advantages, and spreads out the entry times over a day or two to let all timezones take equal advantage.
So, there's not really a gain in the quality of the person who gets to go, but it does call a spade a spade and takes some of the frustration out of the physical process of getting a ticket (if not with the result of the attempt).
edit: I do like non-transferable tickets, however (with some negotiated process of refundable tickets). This can be mostly enforced by essentially requiring will-call for all ticket purchases. While some people might be willing to let you borrow their credit card/id, not that many strangers will. You will have to be prepared to be a jerk and turn people down, though.