I used to use a honing steel frequently for my Zwilling and Sabatier knives, but don't use it on the knives I've made. I sometimes use a leather strop with compound on them and that works pretty well for me to extend time between sharpening.I agree that they work best on softer knives (I have an old henckel probably around 56 RHC that touches up great on the steel).
I use them fairly precisely, holding a consistent angle etc, not flashing them together like some think should be done.
I guess part of the question is about your business philosophy. Places like CPK will tell their customers to go ahead and use the knives hard, they will fix them for free if necessary.
I don't know how many would come in for repair, but it instills confidence even in the more careful user, and no doubt increases sales.
There are obviously some limits what "hard use" should entail. Frozen foods, bones, knife sharpening gadgets and use as a pry-bar are out for kitchen knives for sure. I don't really know where steel rods fall in the spectrum or how useful they would be for a hard knife. This is just a hobby for me, so I have not really thought about a business philosophy. I would probably suggest a strop or ceramic hone instead of steel, though.