"Lighting contactors" are subjected to a huch higher inrush current test. You're not supposed to use 'definite purpose' contactors for incandescent or (especially) HID lighting. Supposedly, the contacts might not last long.
I agree, though .... there are plenty being used as such, and without much trouble. A very common use is to use the contactor to allow a single photo-eye to control many lights. It's also a convenient way to put in a 'test' or 'manual' control.
UL is in the business of testing complete assemblies, rather than the individual parts. Their mark on a component cannot say anything about the finished product.
I have heard of - but not experienced - some inspectors objecting to placing these contactors in pull cans, rather than 'control panels.'