As the distance in question increases, the area decreases proportionately (I THOUGHT cube of distance relative to the inverse cube of the area - but, I don't know - possibly my memory cells are getting rusty). The amount of light given off for each unit of area remains the same. An example: If a measurement limited to a one degree circular area of a gray card from one cm indicates an EV of 10, increasing the distance to the card to 100 meters and limiting the measured area to the same area as before will also indicate 10EV.
Reflected metering will indicate an AVERAGE light output of the entire scene, limited only by the acceptance angle of the meter, which may be one degree, five degrees, ten ... or ?? in "Spot" metering.
Incident metering measures the light falling on the subject - the distance to the CAMERA has no effect. Properly, the meter should be directed, generally, at the camera; it is also useful to point the meter at individual light sources to determine their effect on the entire scene (balance).