That's exactly what I thought I forgot to put on after reading the case's instruction manual...
What do you mean I would get a plastic BBQ if I don't have these on? Are they meant to keep the mobo's heat from the case or something?
This also sounds dumb too, but I really didn't know what to do with I/O panel's "hooks" that (I think) are supposed to be bent inward (or even cut off?) so that they won't interfere with whatever the cable is being connected... So I just left them as they came in the box. What was I supposed to do with them? They rub with cables like ethernet every time I connect them.
I mean you can and will short out your mobo. Use the stand-offs.
And those "hooks" should be bent inward but should contact the sides of your each cover for the I/O ports. It is to make sure everything is grounded so you don't fry any peripherals or the motherboard.