Game ZIPs are uncompressed, why?

If you look in the installation directory of the game (not the user folder!) and go to the "content" folder, you'll see "vehicles" and "levels" folders.
Those are filled with zips, one zip for each vehicle or map.
But those ZIPs aren't compressed. They just store the data like a raw tar file.
I'm just honestly wondering why that is?

When you pack an unpacked mod, it's packed into a zip file with "Deflate" compression as one would expect. And BeamNG is totally capable of loading compressed zips.

I even wrote a Python script that compresses all zips in those "vehicles" and "levels" folders.
I could save a few GBs this way without affecting functionality.

Is this for the sake of smaller patches?

 

Looky here: https://www.beamng.com/threads/compress-asset-files-properly-to-save-data-and-speed-loading.93001/

 

Maybe if there was an option to either zip or unzip the folders depending on you circumstances

 

I, uh, already know you can do that, I said it in my post... I'm asking why they don't ship them compressed as standard.
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Ah well stenyak said it there. Too bad.
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My take is that I/O is often a bigger performance bottleneck than CPU, and compression reduces I/O by making the CPU work...
Something they could consider at worst is implementing zstd, which is the fastest practical compression algorithm.