Wealth and Content are not always Bed-fellows.

Benjamin Franklin (1706–1790) American statesman, scientist, philosopher, aphorist

Poor Richard Improved (1749 ed.)
    (Source)

Borrowed from (or from the same proverbial sources, by) Thomas Fuller (comp.), Gnomologia (1732):

• No. 1771: Great wealth and content, seldom live together.
• No. 5461: Wealth and content do not always live together.

Fuller records numerous other aphorisms regarding contentment not being linked to possessions and wealth.