I always find it interesting that people outside the US think this is a complete joke when really it's just... only slightly exaggerated.
Many gas stations have 64oz cups by default. I haven't seen it in awhile, but the 128oz soda was real and used to be widely available.
I'm from a union family and was in one myself for many years before I changed to a career path where it's proven difficult to organize. You're starting in a good place, but few points.
You have to remember that... a business treating you fairly would ideally be the default, but there's no reason they have to. Your union should be watching out for that for you so that you can focus on showing up and doing your job. The dues aren't for "getting benefits", you already deserve those and those already should be owed to you, the dues are for having someone to fight for you and advocate on the behalf of you and your colleagues.