Its steganography to hide a bitcoin txn from a human inside a hidden channel. But its so simple to hide from a packet inspection engine I wouldn't even call it steganography... for example the "image" downloaded could look like random bits to a person (obviously not a meaningful image) but the packet inspection engine would not be able to determine that.
Huh? No it's not. Humans don't enter into the picture at all except that they are prone to generate things in the normal course of a days events which can be used as carriers (e.g., cat pics.)
Packet engines (inspection, capture, etc) would never be trying to deduce steganographic content from a channel. For the foreseeable future (due to the arms race nature of things) the best they could do would be to fork of likely carriers to other analysis infrastructure.