I think this will start showing up more as the LED luminaires get more popular. If you are paying for the listing anyway, adding the endorsement for storage space is just a small incremental cost in the grand scheme of things. As the NRTLs get comfortable with the idea this should be a fairly simple test beyond what they do for any product and that is pretty extensive.
They blow things up in every conceivable way to see how they fail but even with that, I am amazed at some things that pass.
