You just have to tell them about bitcoin and teach them on how to earn in crypto so that they would be interested in it.
People are tend to be interested in something that they might find useful specially when it comes to money we are always looking for a way to earn some extra .
Thats the reason why the people who you convince decide to join in cryptocurrency because like you said that people need money because money is the basic of life need. Money to buy some stuff and even glamour stuff.