Water is expensive. Especially when you are poor.
“Apart from land – which was actually not a major limiting factor in the village – the main forms of agricultural capital were ox plow-teams (something I’d expect) and wells (something I did not expect). Until the 1960s, the village chief had a monopoly on the digging of new wells, cementing his hold on the agricultural capital; subsequently other families could dig wells, but assembling the equipment and labor meant that those wells were mostly dug by the wealthiest families, with poorer families restricted to a handful of older public wells (though some of these were also restricted, by tradition, to only the oldest families). Wells were used to water crops, but actually the chief value in holding wells was the ability to make water-for-manure trades with herdsmen from outside the villag”
https://acoup.blog/2020/07/31/collections-bread-how-did-they-make-it-part-ii-big-farms/