Are they truly "on", or are they "daylight running lamps"?
My Pontiac Vibe came with DLR lights that would change to full-on lights when it got dark. Or when I drove under a tree. People kept checking their rear view mirrors to see why I was brightening my headlights at them.
Turns out that you can disable the auto-change switch easily. Much better now. It is also possible to turn them off completely, although a dealer won't do it because it is considered a safety feature: go to
DADRL - How To Disable DRLs for instructions.