I think the better question is why, for about 100 years, the phone
> companies have been charging subscribers for the privilege of NOT
> listing the number ... is there some sort of additional effort required
> to accomplish this task?
_Anything_ that that is 'other than the normal practice' has an additional cost/effort associated with it. This applies regardless of the industry, market,or service provider. Telcos, and other regulated entities, are just more agressive than the 'averge company'about recouping those additional costs.. *OR* the profits therefrom, if they can sell it at 'above cost'.