Watching a woman's butt jiggle(not juggle)like jello is not offensive or gross to me or, I would bet,to most men. If you find it gross I would suggest you turn in your man card, if you are a man, if you are female then I can understand your statement.
Disclaimer: If we were talking about Rosie O'Donut or a similar shaped woman I would reconsider the gross part. CZJ type(and ordinary looking) women can jiggle all they want in my presence and I will not feel offended.
To each his own. Somebody needs to take the fat ones off our hands!