Realistically these days with how expensive most of these games are to run and make, if you do not keep cheaters away it can tank the entire project, e.g. Cycle: The Frontier basically had to shut down because they couldn't keep cheaters at bay, in a system that heavily relies on player count to remain healthy and fun. Once the cheating gets bad enough, people stop playing the game, which leads to a death spiral: it starts with bad queue times, which leads to people playing other games, and that spiral further diminishes the playerbase beyond a point of no return. Cycle barely made it 12 months and the result was a multi-million dollar project getting flushed down the drain.
I am glad that Bungie is going with fog of war for Marathon. And heck, given the features Marathon is getting, maybe someday Destiny can have those nice things too. We'll see...
So players of those games are sacrificing privacy for no security at all by the sounds of it.
It's pretty hard to have fun when the server is full of cheaters.
I mean, hard to call cheating in a multiplayer game the same as cheating in a singleplayer game. The former ruins the experience of others, the latter just affects your own session. Hard to be against cheating in a singleplayer context.