Realize also, super simplifying, that at 240V, have 135K across it is about 1.8 milliamps. At 120V, it would be less than 1 ma. That's nothing.
One of the common ways to drive detection on model railroads so that you can determine if a track is occupied or not is to detect current flow through the rails. With more modern control systems where the voltage across the rails is constant, instead of the old variable sort of thing where the voltage controlled the speed, this is pretty easy. A powered unit (with a motor) or anything with lights, that's obvious, there is a load in place. But for freight cars - what do you do? The common option is to put a resistor across the wheels. Most circuits for detection can 'see' with a single 15K resistor, but for reliability (wheels and track get dirty, etc), a more common value is 4.7K per car. I put a 10K resistor on 2 axles of each of mine (most US railcars have at least 4 axles) so it's about 5K per car. Now multiply by several hundred such cars (on our club layout, I will never be able to have that many on my personal layout). Yes, it finally starts to become a somewhat significant value, but when each power supply can supply 5 amps, and you have 4 or 5 of these driving different sections, so only a fraction of the total number of cars is drawing from any given power supply, it's no big deal. With a nominal 4.7k resistance, and a typical voltage of 15V, worst case is about 3.2ma per car. However, less than ideal electrical connections between the wheels and the rails increases the effective resistance. Say somewhere closer to 10K, unless you scrub the wheels and track and press the car down hard. So now we're talking about 1.5ma per car. Even with more than 10x the voltage, this circuit in the power bar is drawing less current than a model train car fitted for detection. You could stick an equivalent resistor in an outlet (don't do this.....) and it won't even get warm. On 240V, it's less than half a watt.
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