(title says it all!) This is game #97301558 on frankfurt
That is a known limitation of the current version. Since there are restrictions for what a player can play, the game automatically disables autobuy. We hope to get this fixed in the future.
Thanks! It makes sense, although a UX thing to consider for the future is the "I don't want to buy anything" button shows up near where the "play all treasures" button is respected, which can lead to a bad misclick!