The engine is already done. "All" they need to do is add new characters. And if someone is downloading the game to play offline, it is not like Capcom is losing money: Sooner or later, that player will want to play online and will have to buy the game or go play at the arcade. Finally Capcom could take opportunity to get the fan made skins and resell them for consoles. Therefore, while Capcom may not win much out of the PC platform, it may help publicize the game in other platforms.
PS: We don't need a leader board, just personal stats. Get rid of it... less work for Capcom. People will hack it anyhow.
PS: my PC user name is "yes4me v2" atm (I don't use the account "yes4me" anymore)