.30-30 99s are actually quite common, but not so common in takedowns. Even those aren't exactly rare.

Apparently the extra 20 grains of bullet weight in the .303 Savage didn't make up for the ease of purchasing .30-30 ctgs, which could at one time be found in every general store, except perhaps in Manhattan.

Savage had a better rifle, IMO, but Winchester had better marketing and brand recognition.