I'm deeply connected to a union with 100,000 members. I've heard horror stories on both ends. One guy got drunk at work, got fired and they got him back his job. Then there is my uncle who was staff for 25 years, his father retired from that same company after 35 years of service and my uncle got run over by a transport truck. No union. Doctor said he couldn't work, company hired a doctor that said he could. Okay so he goes back to work, nope not good enough for them, they want to fuck him for going to a doctor to begin with. They get him to train his replacement, then got rid of his job and had his replacement take over the new job/title. He had no idea. He ended up suing them and won but this is the type of shit these companies pull when you don't have a union to watch your back.