What was the social background of 18th century society?

The society of Tom Jones's 18th century was one in which
classicism, elitism, new ways of community life, and social change was taking
place.

The aristocracy, particularly the nobility was held
on exaggerated high esteem, and they enjoy privileges that no typical citizen could ever
dream of. Those with money enjoyed VAST amounts of it, as well as land and properties.
This led to the often-witnessed fact that the upper classes were idle, ill-educated, and
snobbish to the core.

This, according to the Encyclopedia
Brittanica:

readability="16">

Nobility
The
major European monarchies had no standard of uniform law, money, or weights and
measures. Continental Europe had internal tolls that hampered the passage of goods.
Britain however, had no such tolls. In the 18th century, the nobility of that country
lived in the most magnificent luxury that the order had known. On the continent, the
nobility were wealthy. However, the noble was, to some extent, better off than a
prosperous peasant was. This is because the peasant tended to prosper with the
rest.

So basically Tom, the
foundling, was found by a clueless group of crass class and too much time to waste and
money to spend. This is where the mockery of the story is move
evident.