As Slick Willie said, just move it to the end of the dock and there will be enough room for someone to launch their boat. It would be best if you did that on an outside ramp, like the first one or the last one. The middle ones might block someone from launching if they can't get around you, due to another boat in there, too.

I've had to park on the grass before, (late start) and didn't get a ticket, and have seen tons of other boats do the same. I don't think you would get a ticket either.