Passive voice is one of those things that really irks people for some reason, mostly because their grammar school teacher taught them so. It has a lot of legitimate uses, but the knee-jerk reaction it invokes in people is bizarre.

For instance, there are many cases where one would want to de-emphasize the subject, or cases where the tone should be "passive" in the sense opposite from "aggressive". If you are arguing with someone because you think they are wrong but don't want to put blame, you may want to say "It was wrong to do that" instead of "You were wrong to do that".

Another use of passive voice is for a certain dark style and more mysterious tone. A good example of this is "It was the best of times. It was the worst of times..."