He isn´t just upset with the circumstances of the village, he is actually upset with the circumstances in France. You need to realise that Dickens selects "Monseigneur", Darnay´s uncle, as a symbol of the aristocracy in France. This could explain why Monseigneur is just really a cruel caricature of a person - he represents the attitudes, beliefs and actions of upper class French society. The damage of this is evident in the description of the village in Chapter 8. Note Dickens´style at the beginning of the Chapter - he doesn´t write in complete sentences, but just writes snapshots of what he sees, making it almost an editorial, fragmented style focussing on particular sights as if it were a newspaper:
A beautiful landscape, with the corn bright in it, but not abundant. Patches of poor rye where corn should have been, patches of poor peas and beans, patches of most coarse vegetable substitutes for wheat. On inanimate nature, as of the men and women who cultivated it, a prevalent tendency towards an appearance of vegetating unwillingly - a dejected disposition to give up, and wither away.
Notice how the picture is painted here - poverty and want are features of the village from the very first. The landscape doesn´t have corn but poor, "coarse" substitutes. The people are described as the crops as they have a "dejected disposition to give up, and wither away." This scene is heightened by the contrast to Monseigneur in his carriage - he has a blush on his face, but not because of any sense of embarrassment through the living conditions of his tenants, but because of the setting sun. Monseigneur does not accept or register the poverty that he sees, except to see it as their "lot". Note how later on the country is described as "broken" and then the description of the village repeats the word "poor" many, many times to reinforce the point:
The village had its one poor street, with its poor brewery, poor tannery, poor tavern, poor stable-yard for relay of post-houses, poor fountain, all usual poor appointments. It had its poor people too. All its people were poor, and many of them were sitting at their doors, shredding spare onions and the like for supper, while many were at the fountain, washing leaves, and grasses, and any such small yieldings of the earth that could be eaten. Expressive signs of what made them poor, were not wanting; the tax for the state, the tax for teh church, the tax for the lord, tax local and tax general, were to be paid here and to be paid there, according to solemn inscription in the little village, until the wonder was, that there was any village left unswallowed.
Notice the metaphor at the end of this vivd description: the village is depicted as being literally gobbled up by the various people that are taking money from it. It is this that leads Darnay to reject his inheritance and involvement in this tragic situation. Note how, in the next Chapter, Darnay describes his "legacy":
"... seen in its integrity, under the sky, and by the daylight, it is a crumbling tower of waste, mismanagement, extortion, debt, mortgage, oppression, hunger, nakedness, and suffering."
Darnay, as befits his generous, kind and responsible character, feels culpable for the actions of his relatives and descendants, and thus sees it as his duty to renounce his title and involvement with the situation.