> could anyone explain me, why (the hell) is the snarf buffer in sam
> different from the system-wide snarf buffer (or is it just rio's?)

Hell has nothing to do with it.  1200 baud modems do.  Sam was originally
written for the Blit, which had a 1200-baud connection.  It was decided that
updating the global snarf buffer for every cut or paste would make cutting
and pasting too slow, so sam has its own snarf buffer.

People got used to it, and there are advantages (and disadvantages) to
keeping them separate.  For example, one can have a ready-to-send
compilation command in the window system's snarf buffer and not have
to re-snarf it every time you edit: just sam away, then go to the shell and
hit 'send' with button 2.

But the real answer is 1200-baud history.

-rob