How does Boule de suif criticize the behavior of the French passengers in the coach?

In Boule de suif, Guy de Maupassant uses the behavior of the bourgeois passengers to deliver a sharp critique of their hypocrisy and moral shallowness during the Franco-Prussian War.12

The story highlights the passengers' coldheartedness through several key actions:

• Opportunistic Exploitation: While the "respectable" travelers initially treat the prostitute, nicknamed Boule de suif, with contempt, they readily abandon their social prejudices to share her food provisions during the journey.12
• Moral Cowardice: When a Prussian officer detains the coach and demands sexual favors from her, the passengers prioritize their own convenience over her principles. They actively pressure her to submit to the officer’s demands to secure their own release.12
• Cruel Ostracization: After Boule de suif sacrifices her own integrity to satisfy the officer and allow the group to continue, the passengers revert to their judgmental attitudes, ostracizing her for the remainder of the trip.12

Ultimately, Maupassant contrasts the passengers' shallow platitudes with the authentic principles and generosity of the woman they choose to exploit and shun.1