They do and I kindly disagree with it. Also note they use just a touch of it to get a shine on it before it goes out the door. That's it. They don't use it has a conditioning agent. I would honestly substitute Renovateur in place of VSC if you want to use that type of product on shell to get a shine. Honestly, Saphir Cordovan cream is probably better than all of them because there is neatsfoot oil in it, however it won't shine up as much because it seems there is a lower beeswax content in it, and more oils inherently inhibit shine.
If you want to retain the oillyness of some CXL's and Shell I would use the cordovan cream. I personally use Lexol on everything for conditioning at the moment, but I will be trying out GlenKaren products at some point, which seem to have a lot of logic and science behind them. I only use Wax on the toe and heels, and for shell infrequently a touch of cordovan cream on the vamp over the Lexol, and regular shoe cream on the vamp of calf very infrequently over the Lexol. Again, I will be trying out GlenKaren products as part of this routine as well.
I recently came across GlenKaren too and am considering to try as well. GlenKaren's price is similar to Reno but they are here in the US. That's enough for me to give them a chance.