Bits advocates a standardised, conventional, universal, currency format, accurate to 2 decimal places. Sats has merit, but getting the world to change to a new format is a big ask, it's probably not going to happen.

Other reasons are more subjective; imo it feels right, it sounds right, it looks right; it's a core feature of the Bitcoin technology; at this stage it's value is pretty small, not too big, just right for this stage of the adoption curve. It's easy to say. It sounds digital, and thus self-contextual. It's user friendly.

Well these are a few things that come to mind, I'm sure there's lots more.

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