Paul does not like the soldiers’ brothels, but he succumbs to desire.
Paul describes how the army keeps brothels for the soldiers to use, but he does not like them because they have to “wait in long queues.”
I wish I never thought of them; but desire turns my mind to them involuntarily and I am afraid for it might be impossible ever to be free of them again. (ch 7)
When Paul is with the girls, he can forget about war. When he chooses to “socialize” with the French girls, he feels that the conditions are very different. He can pretend that he has to win her, and picture himself winning the girl from the poster.
The brothel is another example of the cruelty and loneliness of war. Paul may not want to go to the brothel for ethichal and health reasons, but it allows him to forget about what is really going on, and provides him with a short escape where he can feel human.