Things get much more complicated when using it with something like network activity. By nature it tends to be very dramatically large in changes, so the quantity has to be log(x) to make it seem more linear when used in a meter. And since Log(x) has some odd behavior then x<=0, there has to be a lot of conditional stuff to make it work.
Attached should be a gif that demonstrates what I am talking about.
In general it is useful for when the simple motion of the meter (in this case, an analog dial) is enough to let you know something is happening. I suppose that the integral could also be "calculated", but it does not seem to as handy knowing how much data was downloaded