its mainly because he never thought of it. Naruto and his super massive chakra pool allowed him to use the clones in ways most others wouldnt think (instant sage mode, and even practicing rasengan when he practiced with a couple hundred clones at once to learn in days what took months or years). And another point, to those who said he had the chakra reserves. I dont think so. remember, you need your own chakra to be totally equal to the nature chakra, too much of yours and its a failure, too much nature and you turn to a stone toad. So for anyone with less chakra than narutos massive amount to keep a clone active at all times, and keeping it fed with enough chakra to be able to sustain a good amount of nature chakra is a stretch. Also since he never thought to use clones, ma and pa probably taught them to do it that way, naruto just kept screwing up and realized he could use clones after a few mistakes.