Question

which component of grass is indigestible? Don't you think if glass is made digestible in human systems, the food scarcity will be over

Answer 1

Cellulose is indigestible. Yes , grass will be grown like other vegetables and will be sold to the people.

Answer 2

grass consist of roughage(cellulose) which is indigestible in human body since there is no such enzyme in human body that could digest roughage (cellulose). this is the reason that roughage that is present in our food such as Vegetables and fruits passes out undigested.But roughage is still necessary for proper functioning of the gut.

I don't think that if grass is made digestible food scarcity will be over because food is not just a thing that is digestible but something that provides essential nutrients like vitamins minerals etc..
but yes, if grass consist of such nutrients then somewhat it can reduce food scarcity..!