By their hands versus With their hands

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi All,

I heard recently on TV the sentence:

People digging by their bare hands.

Why not with their bare hands?

2

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If it were written, it would be with. I presume that the speaker is rushed or stressed, and s/he would then be liable to say all sorts of not-so-grammatical things.
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