Class action lawsuits help to ensure that defendants can't get away with doing a small amount of damage to each plaintiff, but a very large amount of damage as a whole. There simply would not be an incentive to bring this sort of litigation if not for this, and companies would likely get away with these kinds of only-slightly-harmful practices. By bringing this sort of class action, the damages can be large enough that the defendant is forced to rethink their actions and make a change in their behavior.

Without class action, the damages would be small enough that the company could ignore it (because so few people were suing), or the legal system would be flooded with an inordinate number of duplicate cases in order to bring an appreciable amount of damage to the defendants.

That said, it would be nice to see some sort of restriction on legal fees, or on who is allowed to bring class action suits (perhaps only consumer advocacy groups, as is true elsewhere in the world).