I also wear white eyeliner all the time, on both upper and lower lids. I wear a little black on the outer corners. The white makes my eyes look bigger, and the black makes them look further apart.
If I put too much on, I just wipe it off. No one has ever commented on it. I'm rather fair, and I don't think it's obvious at arm's length.
I think it makes me look a little more finished, without looking overdone. I hope I don't look like a "chav".
Frankly, I'm not sure most people realize I'm wearing makeup at all.