When did you last try to train one? TC? TC has options not present on the live system's creatures.
I trained mine the week after training went live, and never had an AoE option, that I can remember, unless it went away after I picked Armor ignore and/or mortal strike that first level.
The fire beetles have AoE options, but selecting of certain properties make the AoE choice drop off.
Personally, I don't even like most AoE options - most of them make no sense and are more trouble than they are worth (the last trip to Fel I made, one of our party's AoE started hitting everyone but the owner, and the pet would change targets randomly even as all the pets who were injured or their owners were injured turned on it, resulting in all the other pets dogpiling and killing the AoE pet instead of the spawn - just what you need in the middle of a Harrower).
The beetle is a good pet for tanking or holding off groups of lesser spawn, dispatching them one at a time. If you want AoE, you must be only hunting in Tram-rules, or running solo in Fel - because that's the only way AoE is remotely safe.