iTunes?

Does anyone know why episodes of this show aren't for sale on iTunes any more? I don't get the channel they air on, and I'm pretty sure I've watched all the episodes that are on youtube. They were on iTunes for a while (I bought "The Sickest Patient In The Hospital" from season 5 and "The Man With Rocks In His Chest" from season 2). But now they don't sell it anymore :\


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"You can't predict who you'll fall in love with." ~ Taylor Swift