We've got our eye on you. Managers are skilled at pulling workers aside and promising promotions if they stick with management's side. Sometimes the company will actually implement some minor changes in reaction to a union organizing campaign. This is not only illegal, but it also won't last if you don't vote the union in. The boss wants you to believe that management will not bargain with you once you have formed a union.
Facts prove otherwise.
The employer must bargain in good faith. All of the sudden the boss will discover appreciation for the contribution that workers have made to the company. Lunches, dinners, and picnics for workers and their families are not unusual. It is absolutely against the law to even threaten to take away benefits as punishment for a union yes vote. It's amazing how nice supervisors become when workers are organizing a union.