First off, for the particular examples, I don't think there is any difference between 安いから/安いので.
If forced to give a vague reason, the following may be relevant.
Consider
- アップル製品は高いから有名である
- アップル製品は高いので有名である
Both may not be most natural things to say, but 1 is definitely odder than 2 (even if apple products are both famous and expensive), in the same way (I think) in English 3 is odder than 4
- Apple products are famous because they are expensive
- Apple products are notorious for being expensive
(I guess 4 is fairly okay, which is not exactly true of Japanese 2 above).
So ので can refer to the aspect/factor for which the thing is famous, but から sounds more like a cause (being expensive isn't a cause for being famous).
Back to the ones in question, 安いので sounds like for being cheap whereas 安いから sounds because it's cheap. In the particular example, both work, but famous for being cheap is kind of plausible and that's why the corrector made the correction - subconsciously. (Again, note that 安いから/安いので are virtually interchangeable)
I haven't read fully but the following may contain something.