The units you use don't matter. Let's take linear falloff as it's easier to think about.

Let's say we have a scene with a wall and two lights. One light is twice as far from the wall as the other. The intensity of illumination at the wall from the furthest light will be exactly half that of the other, whether you place the lights 1 foot and 2 feet from the wall or 1 and 2 metres.

If you scale an entire scene up, you're changing the distance the light has to travel before hitting an object, therefore the amount of illumination that object receives will change.

Imagine a closet with a 60 watt light bulb inside: it would be pretty bright in there. Now take that same light bulb and put it into an aircraft hangar with no windows or open doors: things would be awfully dark. The output from the bulb hasn't changed, neither have the properties of light. To light up the hanger you either need a lot more 60 watt bulbs or some crazy 10,000 watt monster that would burn your retinas out.

Setting up lighting so that it's physically accurate is one thing, but illuminating a scene so it looks the way you want is something else, and is one of the skills you need in 3D. I'd take the intensity of the table light right down, to the point where it's not burning out the table top. Make the shadows softer. Use supplemental lighting: of course it won't be 'real', but it's what photographers and cinematographers do all the time.

EDIT: I might have guessed that BB would beat me to it with a far more detailed and accurate response!

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