...that the side betters and players are financially unrelated. What I'm saying is that the player is using chips that were supplied by what you consider the side betters. Because these investors have a "vested" financial interest in the chips being used by the player, the player is accountable for the strategy employed.

Shilling may be illegal/unethical behavior in the said card game, but in the business world, the analogy breaks down, because the player (manager) is accountable to the financial backer (who may also happen to be doing side bets on their own). The only illegal behavior involved in the business world is if the stockholders use insider information in their side bets.