Averitt is non union.
UPS is union.
You're more likely to be fired at Averitt, the non union job, then UPS, the union job, this is reality. UPS drivers and all union employees are "fired" and return to work, its union. When drivers/UPS union employees are terminated (actual lose of job), they made a big mistake or multiple big mistakes.
Anytime a union worker says they can be fired for any little thing is a drama queen. A big part of being union is not being fired for any reason, I mean actually losing your job.