Bringing a blending is, in my humble opinion only, one of the most tasteless things you can do.
IMHO, if you want to drink but cannot afford to purchase the ship's beverages, it may behoove you to seek out a less costly form of vacation.
Don't flame. Just my opinion.
It is one thing to bring liquor but to bring a blender so that you can make "home made" foo-foo's

Hahahahaha You can do it. Just don't tell anyone you have done it. Hahahahahah
Kinda like wearing greasy overalls in the dining room.