For an MMORPG, that IS a valid concern though. Pirated copies take up server resources and increase costs. Piracy also makes it more difficult to enforce rules - if everyone has to pay, closing a misbehaving account is feasible, but if a significant percentage of the userbase pirates it, then they can just make any number of free accounts, and degrade the experience for paying users.
Users who pirate applications aren't necessarily lost customers; they might not have purchased it legally even if they couldn't pirate it.