Typically, the lower income people are encouraged to desire the material possesions of higher income people.
One way this is done is to somehow imply or overtly state that higher income, higher status, or higher rank (as in hereditray nobility) people 'won the lottery' and therefore don't deserve what they own. Another way it to state or imply that the higher income people became so only by depriving the lower income people.
Frequently throughout history, nobility and land owners in feudal societies were literally a leisure class and made their living by exploiting the tenants of their land. Land ownership was a matter of fiat, and could only be enjoyed at the sufferance of royalty or of hereditary nobles, whose titles ran with their lands, and vice-versa.
Critics of class envy tactics point out that modernly, the majority of higher income people earned the money themselves.
Some cliches of class envy:
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