Seeing father gambling -> being curious and doing it -> trying too often until adulthood becomes addicted -> losing all valuables and stopping gambling -> returning to gambling after marriage with the excuse of enjoying free time playing games in gambling.
A simple cycle that answers all questions.
a. peer pressure?
b. early exposure to it?
c. social influence?
d. the dream of winning big and have a good and better life?
e. to cope with stress?
OP, should have added "For entertainment purposes"