What is revealed about the upper classes of Marseilles society in chapter 5 (V)?

In Chapter Five, we see the tiers of social class most apparent at the marriage feast where guests are seated according to rank.

Dantes, at the opposite side of the table, had been occupied in similarly placing his most honored guests. M. Morrel was seated at his right hand, Danglars at his left; while, at a sign from Edmond, the rest of the company ranged themselves as they found it most agreeable.

The wedding contract was of no concern because neither Edmund nor Mercedes had property or wealth.

"The contract," answered Dantes, laughingly, "it didn't take long to fix that. Mercedes has no fortune; I have none to settle on her. So, you see, our papers were quickly written out, and certainly do not come very expensive."

Those without social obligations were able to enjoy themselves without the constraint of formalities, and in some cased, threw decorum to the wind.

Around the table reigned that noisy hilarity which usually prevails at such a time among people sufficiently free from the demands of social position not to feel the trammels of etiquette. Such as at the commencement of the repast had not been able to seat themselves according to their inclination rose unceremoniously, and sought out more agreeable companions. Everybody talked at once, without waiting for a reply and each one seemed to be contented with expressing his or her own thoughts.