It makes sense - Richie's tech changes a lot of stuff for him back-stage anyway so it not only helps keep the guitar sounds close but also makes his job a lot easier not having the temporary guitarist having a new rig that he has to learn.

I would anticipate Phil's floor fx board is quite basic for these shows and that the tech has Richie's large board with him back-stage to do most of the fx/amp switching. Just a guess though.