It means it's addictive

When I have true contempt for something, I find in quite easy to quit.

There are things I am likely addicted to that I don’t like. I wish I didn’t do them and could stop, but I don’t have contempt for them. I have contempt for social media and even tell my own mother I won’t join when she tells me it would make her so happy if I was on Facebook.

Alternatively, it may mean that people are largely hypocritical, and evaluate themselves and other people by different standards.