How laughing is used as an insult

Many prominent people are used as fodder for comedic abuse when they can think of no other source material for their jokes. Pollitical figures, celebrities, are the usual targets and considered 'fair game'. I remember when Bill Clinton was president and Chelsea was a teen ager.....she briefly became the 'butt' of jokes until other young people, (my children for example), let it be known that was not acceptable...'don't pick on Chelsea!'