Seeds saving - why?

This is the plant we're saving for its seeds. Sorry, it's a bit overexposed.There is a celery plant in our vegetable garden that reminds me every day how important it is to save vegetable seeds. Celery, unlike a lot of other common vegetables, is biennial. That means that it will only flower and produce seeds in its second year. My pineapple is similar, it produces its fruit in the second