Look up the difference between "past simple" and "past perfect". This is all explained before intermediate English. Where did you find these examples?

It would be used in the construction, "If I hadn't had enough money when they were released, I would (not) have...." That is a subjunctive tense I believe, although I am only a grammarphile and not a qualified ESL teacher. It is not a statement of fact, but rather part of a larger construction. "I didn't have enough money when they were released " is, in contrast, a statement of fact.