Imagine you are visiting a room you never played in before. The majority of the table is obviously regs by the way they are interacting with each other. Now every time you get in a hand with a few of them, they are showing their neighbor (that doesn't have cards) their hand. You can see both of their lips moving, but can't hear what they're saying. Do you feel comfortable staying and playing in that game?
Example: Board is K
10
6
8
2
You have J
9
and have been firing at every street. Now on the river your opponent is still showing his cards to his buddy and decides to call your bet with Q
K
. Are you not left wondering if his buddy whispered that he folded the A
? You should be. As a room manager, that is the exact reason I don't allow it. I don't want new players coming in and feeling like there is shady **** going on here and not coming back or worse telling everyone they talk to that it is a shady place.
Example: Board is 7794K rainbow.
You made a bluff on the river and your opponent is showing his buddy his hand again. He has 78 and doesn't want to call hoping for a chop but after a tank and some lips moving he calls. Did his buddy whisper that he folded the other 7? Did he whisper "you got it". Was his lips just moving because he was silently singing along with that song in his head? Maybe you didn't see his lips move at all or weren't watching. Do you wonder if he somehow helped his buddy?
If this keeps happening over and over, at some point you are just going to leave or call them out. Calling them out probably has no effect so then you leave anyway.