The only times that they have been are during Gavin Verheys special Draft Events and Mystery Boosters

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They cost about $3 and includes four cards, so it doesnt seem like it would take too much to make a profit
Investment Value: Many alt art cards appreciate in value over time, especially if they feature popular Pokmon
He simply says that Magic: The Gathering is currently making a "conscious effort to prioritize having more cards with flavor text", so there's no need to worry about that particular aspect of cards going anywhere soon
I walked over and grabbed one of the playtest decks