That's typical of the lawmakers' knee jerk reaction to environmental pressures and that fact that "yachties" are an easy target.
Victoria BC also discharges vast amounts of marginally treated sewage at a time when these kinds of rules are coming down hard on the relatively small boaters' contribution to the problem.
I think the factor that allowed the coastal regs to be eased was the lack of pumpout facilities available.. I don't think anyone really has an objection to being environmentally responsible, but the tools to comply should be readily available, and at reasonable (or no) cost (other than the equipment on board)
There are (understandably) designated no-discharge zones in popular small coves and parks - and most people do respect these especially if there are shoreside biffies available.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)