"Hanging Out Plant Pot" wrongly Categorized

Correct, but it's not exclusively an indoor plant, so putting it there may be confusing. Another example of a plant categorized under Miscellaneous Decorations is the Bamboo from the Yoga hobby. I think the key factor is that they both seem to be predominantly considered large decor items / statement pieces more than they are considered plants.

There is also a lot of greenery located in the Table Decorations section. But they don't all belong in Indoor Plants because their main purpose is to serve as a decoration. Yes, plants are decorations also, but I'm guessing there's a distinct feature that makes an item more architectural/decorative than organic/decorative.