are carbon seat posts for stick in one position and leave. or for the i like to put it up on the way up and down on the way down. etc

Don't bother getting a carbon post, but as long as you aren't doing too much damage (making it fray etc.) you should be alright.

I leave it where it is.

Not the best material if you like to put it up/down all the time.

yeah..i guess it scrapes of the resin?

It could do, that'll depend on the frame and to some extent on the post. My Soul put some nice scratches into my post so I tidied up the seat tube ends a little and now it doesn't. Obviously gritty dirt might still rub but that mainly just fades the resin and makes it look bad, in the same way as it scratches anodising. But any quality post will have a non-structural top laquer so this is purely cosmetic. People get too worried about carbon, just because it looks ugly doesn't mean it's broken.

Lacquer on mine is a bit scratched is all. Goes up and down like any other post

i used a USE carbon post in my klein for years, it was always being adjusted and was scratched to **** after a while.

when it broke, the aluminium clamp went and not the carbon