I just realized maybe my last post may look harsh, rude, or w/e. Ill explain what i meant. This way is more helpful for everybody:

Whenever you face a decision, and you want to maximize your expected value(of any particular choice), you should not consider past costs. Why not? They have already happened, and there is nothing you can do to change that fact. Instead, what you should consider is differential costs and differential benefits, those that change depending on the course of action you choose.

The above is "Decisions Theory". When it comes to poker it means that whatever money is in the pot at any given time(Say 3bb after both blinds posts and everyone except the blinds fold) is not yours anymore, its the pot´s money and you should not consider your 1bb. In other words that 1bb is a past cost and you should not consider it in the decision of "stealing" the blinds. BTW youre not stealing anything, just taking a +EV choice.