How the #$*@ did you end up a moderator?
1: having a list of addresses and being able to check them all at once has absolutely NOTHING to do with brain wallets Without the priv key you can do nothing with an address.
2: having the ability to monitor a ton of addresses without having to have any keys neither public or private has many uses, if i had more patience with people who are quick to make statements or accusations without first pulling their head out of their @$$ and reading the full OP i might even list them for you.
3: i dont know how in your twisted little head you came to the conclusion that checking balances without keys is for brainwallet cracking. If that were the case, blockchain.info and any other similar service are out to destroy BTC because they all allow it one address at a time, worse they let us explore the blockchain. If there were any logic behind your statement we all better sell all of our BTC as fast as we can as anyone can generate an address in 2 seconds and want to check the balance of it or even a million of them.
Thats an awful lot of very defensive text without any explanation at all. I've encountered inept brainwallet crackers multiple times who had the laughable strategy of attempting a key and querying bc.i for its balance, until they rapidly find themselves banned, then they show up on the forum or chat asking a question a lot like yours a way to query a lot of addresses. Especially when they're asking about querying at a scale compariable to or larger than the number of addresses with spendable coins in existence in total.
In any case I didn't say _you_ were attempting to do this, I asked what you were doing and pointed out what my past experience is with the question (so that you might be aware of the kind of speculation your question might inspire).
Generally if you're seeking help it's advisable to describe what you're actually trying to accomplish so that people with experience can point you to the best solution often when you've found yourself in an unsolvable rut it's because you took a wrong turn a few steps back, and are now headed down a blind ally and only asking complete questions can save you.