Why did indirect taxes on salt and tobacco affect the poor?

Because the tax was added to the price of goods and fell on consumers

An indirect tax is collected through the sale or purchase of a commodity rather than directly from a person’s income or property. When a tax is imposed on salt or tobacco, sellers generally include it in the selling price. Consumers then pay the increased price whenever they buy the product, so the final burden falls on consumption. Poor households are affected strongly because essential goods such as salt take a larger share of their limited income; the same price increase can therefore be more burdensome for them than for wealthy households. Option B correctly explains this mechanism. The goods were not restricted to nobles, and the tax did not provide privileges to peasants. The key idea is that taxes incorporated into prices are passed on to consumers.

This is a Class 9 History question. Chapter: The French Revolution. Topic: French Society During the Late Eighteenth Century.