This can be said about almost anything. Look at a chair, a railroad track or a dog's leash and ponder about the maker's intentions and motives. Almost any product of human effort is worth ten seconds of thought, usually more interesting than with a blue canvas. Singling out paintings for such an argument is privileging the hypothesis.

Very good point - it's interesting to imagine a guide giving tours in an ordinary city showing ordinary things like cars, fences, houses, lamp posts etc. talking about their design and manufacture. If well done, it may be more instructive and thought-provoking than the average art gallery visit! But it would be dreadfully low-status.