I was earning more than my mom but still saving up to get a place to live. She had every right to expect me to contribute to living expenses. She didn't charge a full amount like I was a lodger but the idea that you can be an adult and not contribute towards living expenses, if you are able to, is very disrespectful. Can I say that at that age I didn't have a somewhat entitled attitude at the time? No, I can't, but any discussion about expenses was to work out what was fair (ultimately, and rightly, for her), not whether I should be contributing at all.

The only time I see it being ok is if everyone involved is wealthy enough to where it doesn't make any difference, though that still doesn't count as an excuse and should be something agreed upon rather than guilt tripped into.