Because you have no choice. The vanilla 1.00 disc version is a relic. The patch is required for stability.
Then came Patch 1.04.
If you are downloading Far Cry 2 today from GOG, Steam, or Ubisoft Connect, you are almost certainly playing a version of 1.04. But understanding what you are downloading requires understanding the war between realism and fun. Let’s rewind to 2008. Far Cry 2 launched to critical acclaim for its atmosphere—the savannah heat shimmer, the wind bending the grass, the infamous fire propagation. But it had a brutal mechanic: the "Buddy System." Far Cry 2 Patch 1.04 Pc Download
Stay out of the tall grass.
In doing so, they neutered a masterpiece. Because you have no choice