ConsulCaesar: This is probably due to my lack of technological knowledge, but there is something I don't understand: shouldn't they update the game in order to both change the EULA and start data collection? Especially with DRM-free installers. Civ IV hasn't been updated in a long time.
Updating old games is
very time-consuming and expensive, which is why when it does happen you have to pay a premium price for a "remastered" edition.
Even if they have the original source code, they don't have the original project and environment configurations used by the original development team. The machines they used for development are long gone, the software they used in development is obsolete and no longer supported, and even the slightest variation in configurations can create a cascading effect across the compilation process that can introduce a mountain of bugs. Simply changing the order in which different files are processed by the compiler can have massive effects. This would require an intensive round of product testing and debugging just to get to the game to the point at which you can
start to make your intended modifications. If you're going to go to all this effort, you may as well do a full remaster at that point. For some simple data tracking, it's
really not worth it.
The installers themselves don't change the game, they just install the files in the proper directory on your computer. The original game is unchanged, or at very most some configuration file might have a few lines changed. The actual game code is unmodified, because no one wants to touch it. If you have Galaxy running in the background they can detect when you launch the game and how long you play it, and I'm sure they're gathering metrics on that, but actual data hooks inside the game itself aren't worth the time and effort to introduce.
As for changing the EULA, the specifics don't really matter that much. Every EULA ever can be summarized as:
we cover our asses from all liabilities and reserve all rights. The exact way it's phrased isn't exactly important since, as already mentioned, much of the contract is probably unenforceable anyways. They just want to make sure that on the off-chance they end up in court they have as much legal ammo as possible, and if the EULA is doing that it's not worth having a lawyer spend time to change it.