It's not always that you're not bothered.
There was a time in my life, when we were struggling so much that all we had for food - and household and toiletries - was £25 a week.
To feed 2 adults and 2 children (and 4 cats but they mainly ate the mice that lived in the bathroom and the field next to the cottage!)
I was never 'not bothered' about nourishment. I used to cry myself to sleep every night because I felt such a total failure as a parent.
But £25 a week is £25 a week and all the wishing and worrying about nourishment in the world didn't turn it into enough to fill my trolley with fruit and veg and good meat and decent pasta, etc. I had to put something in front of my children three times a day, 7 days a week AND give them loo roll to wipe their arses AND shampoo to wash their hair AND be able to wash their clothes AND be able to wash dishes...
Please don't imply that those who don't buy good, healthy food aren't bothered about nutrition. It's not true.