I have a spider male and a killerbee who both wobble. It's noticeable. I don't see them wobble unless they're hungry though... I'll sometimes see my spider corkscrew at the front of the tub the day before feeding day ..

My killerbee only wobbles when there's food in front of her.. Otherwise she'll sit there or explore her little tub with no wobble.. I feel like they do it to tease us T.T...