I have 2 thoughts on this -
1) Supply & Demand market forces will sort out what happens with tickets, even the ones snapped up by the scalpers. I know that's little consolation to those fans who feel left out in the cold, but scalpers have just as much to lose as the fans, especially if they get stuck with a bunch of tickets that won't sell i.e. - bad seat location, over priced ticket, decreased demand due to additional concert dates being offered, or additional tickets released for a show previously listed as sold out. Eventually it will be in their best interest to sell those leftover tickets; the trick is to leverage the circumstances in your favor to force the scalpers to lower their prices. In the end it will all come down to timing & research into what ticket options are available.
2) For anyone who doubts the viability of doing concerts in only select cities, I would point to the last concert of the Vertigo Tour in Honolulu, Hawaii back in December 2006. What this showed was that U2 fans from all across the globle were willing to spend money & travel to a vacation destination just to see a concert. U2 fans have proven that they will go to just about any length to see their favorite band play in concert.