One of the common objections of consrevatives to Wilkinson and Pickett's book, the Spirit Level, which provides evidence that more economic equality is better for a society, is to accept that they have found a correlation, but that does not prove causation.
Of course, "proof" does not happen in science, it is a matter of pattern recognition, but there is a body of evidence to back up W+P, and nothing (afaik) to back the argument that the arrow of causation runs the other way, that social problems cause economic inequality.
Several lines of argument that inequality leads to social dysfunction rather than the reverse. One of the clearest is the history of the US and Japan since WWII. In 1946 the US was more equal than Japan, and head better health. These positions are now reversed.
There are other lines of argument which support this view, not least primate experiments where social status is changed and material conditions do not.
I do not know of any studies which have supported the view of reverse causation.