The glue is what holds the whole thing in place. just leaving them there unglued, the bass is going to still flop back and forth.
I still haven't super glued the bumpers i got years ago from Paul for my non-Wal branded hiscox and it holds fine. The "pillows" on the top lid of the cases holds it down while the bumpers prevents it from going side to side.
I guess if someone is walking and swinging the case like a madman they'll be some shifting going on, but testing it out, I don't hear any movement.
Here's a pic example of my case with an mk1 and mk3