We're talking about people who struggle to pay for easy access to clean drinking water here.
Clean drinking water is actually really cheap in the developing world, they just are resistant to non traditional methods. Everyone wants water systems, no one wants clorine. Guess which one is way cheaper? But it's not really weird that people act that way. Here in the USA we kill ourselves with unhealthy food when we could easily cook healthy stuff.
Part of the issue with that, is that the typical american household does not have much "quality time." Cooking a good, wholesome and healthy meal requires an investiture of energy and care/concern. You have to WANT to cook the food, and WANT it to come out beautiful and delicious.
Typical american households these days have both parents working, they come home and have approx 2hrs of free time before they MUST be asleep, if they are going to get the necessary 8hrs to recuperate themselves. This 2hr window is vied for heavily by everything from television marketers, to the kids asking for help with homework, to getting basic chores, like dishes and laundry done.
This leaves shit little time for proper food preparation, and is why the clearly inferior GARBAGE that you can get at the grocery store in a paper box is appealing. "Heat and eat! Ready to serve in under 20 minutes!"
This is mostly cultural. In the US, there is a cultural stigma against telling your bosses, in no uncertain terms, that "Mandatory overtime" is "Fucked up, morally repugnant, and the only reason it is being done is to drive your bottom line because of your inept long term planning." (Mostly because doing that would result in your getting fired, and there being a steady stream of eager people who are willing to capitulate to the boss's desire for extra labor without hiring more hands, waiting in the wings to replace you at the drop of a hat.)
In countries where family time and quality of life of the human are more enshrined, that kind of shit does not happen, and culinary and cultural aesthetics flourish.
Places like France.