pros limp in cash games for a few reasons.

I think #1 is trap. Limp with big hands, not only to disguise them but to reraise squeezers. Also hands like QQ JJ are much more vunerable in a cash game.

#2 is to vary thier play. Thats it, you cant raise every pot you enter, your gona squeezed.

#3 Value. In cash games getting in cheap ios a big part of that stratagy for players who like to play alot of hands. You just lose to much value raising all your suited conecters. Folding them is out of the question though, you need to pla hands that make big hands or the nuts to stack people. Honestly unless your opp has an under paie and the board is dry, your not gona do alot of stacking with AA or KK. 76s though your eaither gona fold, or drive Vil to value town, one way.

6 max is tricky i guess if you never OL'd you wouldnt be too far off from optimum play. Just depends on your image. 6max i probly play 28/18/4ish. I guess i really only open limp when i have a big hand and im expecting to gt squeezed more then 75% of the time.

How about this question.
Whats worce open limping or cold calling. why?