That would have unraveled the whole 'Prince of Peace' message and turned it into 'Prince of Slaughter'. Probably not as effective a marketing tool as allowing potential converts to live to be converted into Christians...saved, savior, etc, etc. The language of forgiveness vs the language of revenge. Oh, the message of giving eternal life plays a big role also...."Ye shall never die" was a big selling point.
Isn't that supposed to be the plot line of the sequel so many evangelicals think is coming out soon?