As a teacher, I’m often asked this question in one form or another. Mainly, I teach people about computing and I’m often asked “why should I learn to use a computer?” My serious answer is – “because if you want to communicate with younger members of your family you need to use a computer or smart phone and if you want to find information about almost anything you will find it online”. My more facetious answer is simply “because it’s fun”.
You could say the same about learning to play bridge. Why should you learn to play bridge? Simply – “because it’s fun”. More seriously because there a range of health and social benefits – which you can read all about here – “Why Play Bridge?”