I only skimmed the posts, but here is my opinion (based on my 19 years of training - 17 in a commercial gym) on what I did absorb.
If two guys (strangers I assume) are actively using the machine then I'd use another, or ask how much time left untill they're finished with it. It's 3 minutes - I'd politely wait for up to 5 minutes, then start being slightly obnoxious in a non threatening way - i.e. spill my water, trip on their gym bag, ect. LOL.
If it's 2 guys joking around with a machine, then I'd ask to work in, and pile on the weights so they'd get tired and they'd leave. If they wouldn't let me work in and I had to wait more than 5 minutes I'd force my way onto the machine and they'd have to complain about me. Being a 300 pound world champion deadlifter has it's perks - I can win a who's the bigger asshole contest - lol. We have a side door to the alley, that I've never had to use, yet.
Under no circumstance's would I be the one complaining to management about member behavoir problems. To me that's snitching, and it's also failing to negotiate a solution of your own.
The solutions I've described are based on real life experiences and are very few, and really far between.
The more serious about your training, and the more serious the people you train with are, the less problems arise. It's about one Iron Warrior respecting another. Black, brown, white, asian, democrat, republican, man, woman, gay, straight - in the power pit we all get along, and help each other to excell.
It's really America at it's finest.