Along with everything that everyone else has been saying, and I think this has been mentioned already too, it's not all that easy to hear about tours in the first place. The extreme tours get a pretty big publicity push, but the more prog/power focused stuff really doesn't. The best thing to happen in this regard lately is Enter The Vault. I don't know how many tours came near me that I missed simply because I never heard that they were coming. I know I missed a Dio/Hammerfall matchup once a long time ago. At least I think that was the package. I generally read BW&BK's site and get ticket alerts from Live Nation/Ticketmaster, but that doesn't cut the mustard for getting the word out.