MaryEliza, I have wondered that the guests on the JK show generally seem to be the poorer sort of people. There are usually multiple causes for any events. The motives imputed by some of the grans are very likely true; fame for a day, free hotel accommodation overnight, the glamour of telly.
As for the audience, at home and in the studio, although some people gloat others want to understand more about human nature and the troubles we get into. It's the same with gossip generally; some gossip is malicious and some gossip is sympathetic. I , like so many others here, (although they seem not to recognise the fact) have been lucky not to have found myself homeless on the streets and maybe turning to drugs as my only escape from hopelessness.