One interesting physics way of looking at it could be that the energy of your motor (or the wind in the case of sailboats) displaces water as a function of the mass of your boat. The mass of the displaced water multiplied by its acceleration creates a tremendous amount of force. (F = MA) Hence, "no wake zones" exist.

Any boat operator who does not keep that in mind could find his progress altered or stopped — by other people angry about the force of the wake.

And I just thought of a useful sailboat analogy. A sailboat's rudder is an amazing thing from the point of view of physics. Using a rudder, a sailboat can harness wind coming from the "wrong" direction. Sailors love a "beam reach" sail. The wind comes in at about 90° from the desired course of motion, and the rudder under the boat displaces water, essentially creating a powerful wake under and on top of the water that causes the boat to move in a different direction from the wind. The wake is literally driving the boat.

Also, while a sailboat has a very good ability to move in directions contrary to the wind, it cannot beat directly into the wind. So sailors "tack." They zigzag. They use their rudder to direct their wake so that they move first 45° to the starboard of where they want to go, and then 45° to the port of where they want to go. They keep that up until they eventually get to where they want to go. (This is a simplified explanation, and the degrees are arbitrary and not always what are used in real sailing.)

Again, the wake is driving the boat. Literally. The water coming off the rudder is directly analogous to the force of a jet engine or a rocket. If this were not so, sailing would not be possible except directly downwind, and humans would likely never have learned how to cross oceans.