GE LED PAR 30L Narrow Flood Bulb - I'm confused.

[middle.road]

Picked up (4) of these dirt cheap at a local discounter.
So I tossed one in a old desk type lamp - worked fine.
Dang they are bright!
But...
There is a in-line fuse holder in the bottom of the box.
I did finally read through the instructions but I don't get it.
Do I need the fuse in a standard fixture?

........

 

[jwmelvin]

Calling it a misapplication fuse makes me think it’s to blow if one replaces the LED with an HID bulb (which would need a ballast)?