If the real reason is just to offset the tax on "necessities", why not simply make them tax free in the first place
If the objective is to not tax necessities, then why not simply not tax those items in the first place?
Who gets to define necessity for you?
The FCA mechanism allows you the individual to define your necessity by your situation and actual purchases. Exempting particular goods leaves the choice to the government via lobbyists pushing advantage for their client's particular "necessity."
Personally I prefer to make the choice of what constitutes necessity by what I actually purchase than by what Politicians or worse bureaucrats by arbitrary regulation choose to allow for "tax free" purchase.
The existence of such a system (and the associated bureaucracy, which would have a scope just as wide as that of the IRS
The bureaucracy and data already exists with no addition to scope, and without the IRS. The Social Security Administration, where the legislation places that responsibility of receiving application for the FCA in accord with household size measured by number of legal residents in the household.
I fail to see any new, and infact a reduction in bureaucracy under the FCA mechanism of the NRST. Making specific items exempt instead of FCA, does nothing to change the bureaucracy required whatsoever. Exempting particular good through political processes does ,however, assure that you'll be paying taxes on things that you personally consider a necessity in your particular situtation.