Initially, I thought the same, but if I were the owner of the business where this jerk worked, I would not want this guy working at my place of business either - if he attacked a customer while working for me, who’s going to pay? Me, the business owner!
So, I think his employer had good grounds for firing him. He didn’t just argue, or give and opinion, he stole personal property and threw a drink in a teenage kids face just because he disagreed with him.
The owner better watch his back and hire a night guard for the bar. This jerk seems the type who would want revenge for being fired.
If he had been drinking from that drink, even with a straw then is possible that the man’s saliva was in that drink and there-fore deposited upon that teen. That’s why an upgraded assault charge must be applied and possibly hepatitis and STD testing should be done!(If it hit the face especially)