Most class action suits are scams anyway. Just today I received notice of one that I'm included in being filed against Netflix for alleged privacy violations. The lawyers are seeking $9 million. I won't list the whole breakdown of the proposed settlement, but the lawyers are keeping $2.25 million (not including expenses), while the plaintiffs get a whopping $30,000 to split between however many thousand there end up being.
If Valve screws you over, you can still sue them as an individual, this just limits the ability of glorified ambulance chasers to make outrageous amounts of money in exchange for getting their supposed clients a settlement worth less than the cost of a good meal.