For single-player games, developers lose a sale. However, for multiplayer games, the Spacewar crack actually creates a strange ecosystem. Some indie developers have noted that "Spacewar players" (pirates testing the game) often buy the game later for the workshop or server browser. Other developers view it as a parasitic drain on Steam's Relay servers (costing Valve money).
The "Steam Spacewar Crack" is a fascinating artifact of software archaeology. It is not a crack in the brute-force sense, but a Steam Spacewar Crack
Because it is Valve's official testing ground, App ID 480 has privileges that normal games do not: For single-player games, developers lose a sale
This is why the "Steam Spacewar Crack" is specifically vital for: For single-player games