Now that the average home can have several computers, tablets, smart phones, digital cable boxes, digital TV sets, cable modems, network routers, and various smart appliances in addition to multi-channel home audio systems, it may be time for building codes to step out of the 1960's and recognize the new world order. Perhaps we should be putting whole house protection into all new construction. Or, if codes don't require it, builders should certainly consider it. As you noted it's cheap n easy to do and could easily become a feature that could be marketed to prospective buyers.