They are a segment that has a life so good that they have free time to always be on the lookout for something that is racist / sexist / homophobic / nazi / whatever-other-overused-keyword-you-can-think-of-ist.

This ^ I completely agree.

There are a growing number of people who spend most of there lives actively looking for ways to get offended.
Deep down most feel lost and have low self-confidence and finding offence like the examples above is just attention seeking.