Why humans have to « please » for something ?

Why humans have to learn since kid to “please” and to beg for something.

Isn’t normal to them to care of each other’s ?

 

Snails love « thank » them each other’s, but they don’t know about the word « please ».

I learned it from humans. And I still have a lot of difficulties to properly understand this word.

In a world with a collective issue « please » don’t make any sens because : what is good for others, is good for me as well.

 

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