Don't be too quick to keep your hunting buddies away from your stand.
You do have a problem if you are walking into your stand and they are already there. Then I would sit down and talk to them.
But, if your "problem" is that they come to your stand while you are hunting...is that really a problem?
Think about it...while they are walking around, they are moving the deer. I wouldn't encourage them to visit every hour but one or two times during the mid-day might be a good thing.

ALWAYS CALL YOUR SHOT.