That's half price afaik. Anime volumes are generally around 70 USD in Japan. It also matters how many episodes are in each volume. Typical shows should be around 30-35 dollars an episode.
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SnK 32 spoilers - This scene's animation was beyond good. https://sakugabooru.com/post/show/34352
The animation in the entire episode was bliss, but holy shit that scene.