I 've run into following examples as an illustration of how the dictinction between restrictive and non-restrictive uses of relative pronouns matters.

(1) There were few passengers on the train who escaped injury.

(2) There were few passengers on the train, who escaped injury.

Apparently, the point being made here is that (1) implies virtually all on the train got injured (which I believe is a correct interpretation) whereas (2) implies that a) there were almost no passengers on the train (which I belive is a correct interpretation) and b) those very few who were on the train nonetheless escaped injury.

To me, (2) sounds odd because the focus of part a), which is the near absence of passengers, clashes with the focus of b), which is the existence of those who were on the train (and escaped injury). Come to think of it, since it is difficult to distinguish between (1) and (2) in speech (i.e. you don't articulate a comma!), my guess is that (2) is taken to mean (1) in the actual world, both orally and in written from.

Any comments from the native speakers?
The comma in sentence 2 makes it look more like the train escaped injury. If the point was that there was a small number of passengers, the sentence would need to be rephrased.

There were few passengers on the train, and they escaped injury.
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You are right about the practical use of those sentences.
However, recall that the purpose of the sentences was just to illustrate the difference between restrictive and non-restrictive relative clauses. Sometimes those who want to illustrate a point are so focused on that particular point that the example they choose may be a bit unrealistic in the matter of authenticity.

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