You anecdote doesn’t mean anything. Poor people might be more likely to fake being happy so they can avoid judgement or any other reason to fake happiness.
It’s been proven in several studies that income is linked to happiness.
Happiness is a choice. Being poor doesn't mean your sad all the time, it means life is tough, tougher than the lives of the rich. Even in the toughest of times, there is plenty to be happy about.