Well the only solution at a conference is to not rely on Wifi, seeing as how it's pretty terrible once you get 3 or more devices using it at the same time. Honestly I've rarely seen wifi even sort of work at conventions, as the networks, even for tech conventions, are generally just set up poorly. Adding in the rather obvious deficiencies and scaling issues inherent in wifi, and you just end up with a bunch of noise.
And the limitations of wifi are such that in a hostile environment (if the report of 570 wifi networks is correct, then 'hostile' is an understatement) no amount of determination or equipment can give you a functioning network. For instance, the Defcon network has gotten pretty solid these last few years, but it can still be brought to it's knees by a script kiddie spamming deauth packets. And there's just no way to stop that sort of thing.
Even on an ideal and uncongested network consisting of a single access point and a single client, almost half of the bandwidth of a 802.11G network is consumed with error checking and transmission control to make the network behave like a wire. Add in more clients and you get more air time chewed up by control packets, less available for data. Multiuple networks on the same (or overlapping) channels degrades your data/total ratio even harder, as they all negotiate for air time. In general, even with the MyFi deals, you have an average of more than one client per AP, which brings the total wifi devices count to over 1000. That's just entirely unreasonable. I imagine most devices just quit trying.
Which is why I'm glad I can tether my phone to my MacBook w/ USB.