Re-read lines 291-306. Why is Mrs. Frank concerned about the legality of the ration books?

The reason why Mrs. Frank was concerned about the legality of the ration books was:

Because she always conducted her behavior under the law, even when she suffered from abuse. She was being honest.

Explanation:

In those lines Mrs. Frank let us know that she had a conflict of breaking the law because she had always followed it, even when people broke the law in certain aspects when they interacted with her. Showing up a big conflict she had for being honest when people didn't care about being honest and just with her.