Thought I'd share a couple of stories and see if you've had very similar incidents, not just any confrontation, but launch hogging incidents. These are from the past 3 years or so.
Mountsberg:
Two places to launch. The trailer launch which is located along that path and then really close to it there is a small open area clear of bush and trees that is a natural access points for small boats.
I have an inflatable and the launch ramp path was full of cars along the sides. So I couldn't drive in there and blow up my boat and all that business. So I did this at the lot up top. Then I walked down the hill to that natural hand launch area, where two guys were sitting down and fishing.
I politely asked them, with a smile too, if they could shift over a bit and allow me to launch. They refused. I think it was old father and adult son. Father was silent but son straight up said no way, you're going to disturb the fish. I said you're sitting in a place that a lot of people launch small boats from. He said he didn't care. Go use the trailer launch. I told him it was full of cars in the first place or else I would have set up and launched from there.
Not wanting to escalate to confrontation because my gf was there, I had a few words for them and I had to turn the inflatable sideways and squeeze it through that path full of branches sticking out to get to the ramp.
For those familiar with Mountsberg, you know the spot I'm talking about? Do you think it's fair game for anglers to just occupy the only natural hand launch area, albeit not a designated launch, and refuse to move? Though at the same time, there are lots of lakes that don't have "designated" launches. No signs. They are the obvious spots and people understand.
I have no idea how long those guys were there for and if they had or hadn't seen canoes and kayaks try to use that spot but I have seen people use that spot a few times in the few occasions I've been.
Ken Whillans:
There is a clearing close to the parking lot that is the obvious launch for the small boats here, which are the only kinds of boats allowed.
I blew up my boat in the lot and started the process of moving my gear the 15 yards or so to the launch. The first thing I brought was my rods. I dropped them on the picnic table and a guy rather rudely says "Excuse me! I'm fishing here." I said, ummm, okay.
I actually didn't realize at that moment he didn't realize that it was the launch. I then said I'm launching my boat here. He then understood and said sorry.