Absolutely. I already said you can earn points via favor to redeem for AS.
Selling on the Shard exchange also works, but something you seem to have not considered is that the people buying your items got their shards from somewhere, probably purchased. You're living in a fantasy world where people just grind points and spend them exclusively on AS. I can tell you that NO ONE I know does this. You can also unlock 99% of the game for free grinding favor. Like 4 people have done this, ever. It's mind-numbing. Possible? Yes. Likely? Not at all.