According to SJT, this is because, for the disadvantaged, satisfying their inner yearning for predictability (and control) via support for existing arrangements may come at the expense of relinquishing their struggle for equity/equality (i.e., group interests), and these competing demands are likely to cause cognitive dissonance (Festinger, 1957) — a psychological dilemma that people are often motivated to eliminate/avoid.
exploredata-ZA5400_VarV66 exploredata-ZA5400_VarV53