Sometimes distasteful, irritating, unpleasant, repugnant to the moral sense, lacking class/good taste/grace, uncouth, or disagreeable to some; but extremely amusing, interesting, humorous, or hilarious to most.
Person A is causing a ruckus
and being outlandish
Person B: "That guy sure is a mess, but it's really funny! What he's saying would surely be offensive if I actually cared."
Person C: "I'd say he's mildly offensive, highly entertaining."