Breaking cauldron with Silk Touch results in 2 drops

While playing on friend's realm, I've decided to raid a Woodland Mansion. While collecting various blocks from that place, I've noticed that breaking a cauldron with a Silk Touch pickaxe will result in 2 cauldron drops, while breaking it with normal (unenchanted) tool gives player 1 drop. You can see it in this video (uploaded to gfycat because of file size restriction):

https://gfycat.com/TestyRegularHarborporpoise

I'm not sure if this can be tagged as an exploit, since it allows for duplication of a certain item.

Greetings