I agree it makes good sense to keep all downstream receceptacles of a GFCI limited in number and very close by. I generally follow amp-man's example of installing one at each outlet.
However I can't find any code, listing, or other information saying you are limited in the number or proximity of downstream receptacles.
In the NEC GFCIs appear to be treated like any other receptacle with respect to how many.
I looked in the UL 'white book' and 'green book' [category KCXS] and there is no mention of 'how many' on a circuit.
I have Pass & Seymour's 'Installing and Testing a GFCI Receptacle' instructions - no mention of 'how many' on a circuit.
If there is any such limit as to 'how many' it must come from a particular manufacturer.
