This concept applies to a lot of the higher end builders as well and to me is very subjective.
Just because they don't accept custom orders now, doesn't mean they can't create high end custom cues. There are a lot of Fancy SW cues made in past and present but unfortunately they are not always on the market (average joe probably can't afford a custom cue from SW).
Hercek, Benders, Gina and every other high tier cue builders also have their based cues that you would called "Not Custom Cue" because it applied to your concept of modification to their standard formula in term of woods, veneers, taper, etc. Does this mean, they are not a custom cue builder as well? or only specific cue can be a custom cue?
If we defined custom cue as a personal item such that the designed is unique to your spec, weight, length, balance, etc, than...there are very few custom cues in the world. Custom would only be cue that are made specifically to you and if you bought it second hand...it no longer a custom cue...only to the original purchaser. In most case, the buyer only choose woods, veneers, taper, etc...and in some cases...the type of inlays...which again are fixed to what the cue builder have available in their inlay design template.
Duc.