How come you are reading this?

Will someone please tell me- how can ‘how come’ be correct English usage? Nowadays, I see it being used as frequently as ‘Hello- how are yuh?’ out here. I also spot it in newspaper articles, letters to the editors,et al.

Initially, when I heard some friends using it, I thought they were paying tribute to the Red Indians of yore, who would say ‘How?’ instead of Hello, and, probably used ‘How? Come!’ as a way to say hello and invite people into their teepees without expounding much of their energy by saying ‘ Hello and welcome. Please enter our humble abode’.

Various examples of ‘How come’ that I keep hearing:
‘ How come he said that?’
‘ How come you did not arrive on time?’
‘ How come he does not enjoy life here?’
‘ How come (s)he did not come when I did?’….LOL.. err, no, I made that up…credit that to the light-hearted mood I’m in, today.

Speaking of English, I saw some more examples of fractured English recently, and some of them are just so ROFLworthy that I must share them with you. All are supposedly spoken by teachers/principals:

Principal to student..." I saw you yesterday rotating near girls hostel pulling a cigerette...? "
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Class teacher to student:" pick up the paper and fall in the dustbin!!!"
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Hindi teacher "I'm going out of the world to America.."
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Another teacher:"..DON'T TRY TO TALK IN FRONT OF MY BACK.."
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Dont. laugh at the back benches...otherwise teeth and all will be fallen down.....
(My remark: I can believe that this one was really spoken)
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Teacher: (When the classroom fan did not start in summer)
" why is fan not onning"
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Teacher in a furious mood..."write down ur name and father of ur name!!"
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Chemistry HOD comes and says"My aim is to study my son and marry my daughter"

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"Tomorrow call your parents especially mother and father."
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"Why are you looking at the monkeys outside when i am in the class?!"
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- Computer Lab assistant (when the student wrote the wrong code)
"I understand. You understand. Computer how how understand??
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Seing the principal passing by, the teacher told the noisy class.."Keep quiet, the principal has passed away"

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Quiz for today:What does this refer to::

Two individuals proceeded towards the apex of a natural geologic protuberance,

the purpose of their expedition being the procurement of a sample of fluid hydride of oxygen in a large vessel, the exact size of which was unspecified.

One member of the team precipitously descended, sustaining severe damage to the upper cranial portion of his anatomicalstructure;

Subsequently the second member of the team performed a self-rotational translation oriented in the same direction taken by the first team member.

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Thought::Just because you're paranoid doesn't mean they're not out to get you.

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Till next time,keep smiling!!