>>But how rude. I mean if someone doesn't want to explain why can't they keep quiet? Posting isn't obligatory.<<

I can think of three possible reasons: 1.) They do want to
show off. 2.) They want to give others a learning
opportunity (this is the least likely of the three, I think.) 3.) These things are so familiar to the users that they use them without even realizing that not everyone
knows what they know. (Oh dear; too much repetition!)

>>I wonder why some people prefer to ask somebody else and others prefer to look up whatever<<

My opinion is that this is just due to the person's characteristics: whether he/she is self-confident, fearful, social, more of a loner, etc. Perhaps the
supposed reluctance on the part of males to ask for
help is due their feeling the primeval need to be the infallible bringer-home of the sabretooth, etc.