I agree with a lot of this. I should add that I am somewhat conflicted as I've been heavily involved with campaigning for cheaper football tickets down the years. I'm also massively opposed to dynamic pricing for gigs and it would've been great if Oasis had railed against that from the off rather than agreeing to it. In their defence (if you can call it a defence), they're far from alone as the likes of Springsteen and Coldplay have, in the past, agreed to dynamic pricing for their gigs too. To that end, they can't be accused of giving any less of a fuck as Bruce Springsteen and Chris Martin but for some reason Oasis seem to be getting a lot more shit for it than those two.
Dynamic pricing issues aside, I agree wholeheartedly with your post. Gig prices are high pretty much everywhere these days but gigs are different to football matches in that many football fans attend 20,30,or 40 matches a season, whereas you'll be hard pushed to find even the most diehard Oasis fan who has attended 20,30,or 40 Oasis gigs in their lifetime. Put another way, I went to see The Killers at the Co-Op Live in June and my standing tickets were £103.50 each including booking fee. If City charged that for a CL QF or SF I'd be far more inclined to kick off about that than I was when I stumped up the money for my Killers tickets. That's partly because I attend every City home game when I'm around to do so, but I've only been to 7 or 8 Killers gigs. I spend far more money on football tickets every year than I do gig tickets.
Apart from the dynamic pricing, I don't think the Gallaghers have shat on anyone really. They've got to where they are through their own efforts and they're clearly reaping the rewards of that. I'd challenge anyone on this forum not to maximise their own popularity if they found themselves in the same situation as Liam and Noel. Questions definitely should be asked about the dynamic pricing but beyond that, they're getting unwarranted stick compared to many other artists who charge a fortune for concert tickets too.