I mean, do they really need to rotate setlists if they’re playing Philly one night and Cleveland the next? The chance of overlapping fans will be so minimal and both cities may miss out on songs that realistically won’t likely be played live again after the tour. They still rotate from leg to leg which is a lot more logical
I think you have to look at it from the standpoint of the "what is coming next?" factor, and to explain that, in the modern day internet age, most set lists from bands that have any kind of following are usually online pretty quickly, so it is easy to for fans to check them out. So, going to a concert where you know the exact set list ahead of time takes a little of the fun out of it. Now, it is easy to say, "Well then, don't look at the set list ahead of time," but that is not realistic for most, so I think it is better served for artists to adjust accordingly and keep them a little fresh from night to night. Not saying every night has to be completely different, but I think having those a handful of spots that can rotate is the best of both words. I can say with great confidence that concerts are far more exciting in general when you go in having little to no idea what the set list is. Take when I saw Radiohead in the late 00s. IIRC, they played 25 songs a show, and probably 16-17 spots were the same song each night, but even those often bounced all over the set list (All I Need was our opener, but I think that might have been an encore the next night for all I remember), and then you had roughly 1/3 of the show being different each night. That was awesome. And using the stage show thing as an excuse to not rotate at all doesn't pass the sniff test, as bands like U2 and Pink Floyd have done massive stadium tours in the past, with lighting and screening shows far more elaborate than anything DT ever could likely afford, and had variations in their set lists on a nightly basis.