How about the issue of where these songs fit in your average setlist, especially now new material exists, and how well they would work in terms of entertainment value? To create the best possible show, appealing to as wide an audience as possible, you need a setlist with some variety, with a least a few crowd-pleasers.
They make an effort to keep the crowd engaged - some would say too much effort, in the case of Bruce talking about buns in ovens during Phantom of the Opera recently. SIT is very popular in these parts, but what is the wider fanbase reaction to SIT tracks other than Wasted Years?