Sylvania 9006SilverStar ZXE GOLD Halogen Headlight Bulb 2 Pack

Ordered new Silverstar Golds for my driving light (DRL)/Highbeams and after three years sill going strong! Reason for replacement of the other Golds was that I installed new headlight assembly and wanted new bulbs threw the housing, that I need to not worry about pulling everything apart again to replace any bulb. Excellent Halogen Bulb, I probably averaged about 2.5 hours of DRL and highbeam function for 5-6 days a week for the last 3 years. The DRL never got yellow, it stayed white! Ran into the gas station few months prior to the bulb change, left the car running walking back out and looked at the DRL light and it was still a WHITE light that did not get a chance to yellow over 3 years of service. I've always been very pleased with Silverstar halogen bulbs for the last 15 years or so. Never had longevity or performance issues, of course I use disposable gloves while handling any type of bulb especially HID's. Why do people put LED's in a Halogen housing? Isn't it illegal?