Did you know the job paid minimum wage when you took it? I’m not following the logic that the boaters are obligated to make up the difference between the pay you agreed to accept and the pay you would like to get.
I imagine he was told when he took the job that there would be tips. Not told by boaters but by the owner.
Honestly, they perhaps gave him the title dockmaster, but the pay of less than a dock hand. To me a dockmaster runs the marina operations and has staff under them.
If our minimum wage was a living wage, then we wouldn't have the issue he had.
Had I gone there and he been the one helping with no other dock hands, then I would have tipped him generously and without any reservations or feeling any pressure, just out of my own desire.
I'm going to add one statement: If in doubt and you can afford it, tip. Do it out of your own generosity and appreciation. It will make two people feel better, you and the recipient. If someone else has an issue with it, it's not their money, they aren't involved, and it's not really any of their business.
Really the same looking at professions we don't normally tip. It's your HVAC guy at 10:30 at night or your plumber on Thanksgiving Day and you want to tip, do so. Then, even if they say they aren't allowed to accept tips, you made the gesture and they know your appreciation is real. My father was a CPA and I remember one client wanting to tip him. It was a new client whose prior CPA had told him to go on and pay a penalty of $80k and my father got it reduced to $3k. My father wasn't insulted by his wanting to give him a part of what he saved, just not the way he did things.
When we're talking a dockmaster, I'd have to know the set up and situation, but if he was the only one helping during my stay, then I'd try to tip. Generally though it's dock hands and here I am able to afford a nice boat and they're working hard to make things nice for me and can't afford any boat and I'm glad if I'm able to help them out.
Our most generous tip ever at a marina was Nicaragua. We were treated like royalty from the moment we arrived. We did get a driver to take us through some nearby areas and saw how people were living. We got to know many employees at the resort the marina was part of. We knew the dockmaster had a large extended family he was helping as he was the best off by far in his community. We can't solve the extreme poverty and squalid conditions there. Those who worked at the resort were the elite and they did share and help those around them. Do we sometimes tip out of guilt? Perhaps but nothing wrong with that. I do feel guilty people have to live like that and if I can help a little, then I will.
I see people at restaurants or driving taxis or as bellhops or working at marinas, working hard while I relax, largely because they didn't or haven't yet had the educational opportunity I had. Equal or better people than me. I feel fortunate if I'm able to help them a little. For those of you who don't tip, that's your choice, but you're not going to stop me and not going to make me feel guilty about it. I'll also risk tipping where it may be inappropriate and if someone wants to decline it, then that is fine. Have tipped in many countries around the world with no problems.