Perhaps the man did not ask you politely to stop pointing the sole of your foot towards someone and that annoyed you.

However it is considered rude so you can remember that in future. I'm sure you're not the type of person who would make a point of being rude.

Some people find it rude and some don't. I think it is mentioned in most etiquette/guide books in the Gulf. Personally I try not to offend and make myself aware of local customs on my travels.

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