How important is the rear sway bar?

I'm pretty happy today because I finally fixed the squeek noise that came from the rear passenger side for a while now. It was the rear sway bar that's making the noise.

I did some searches and found out that rear sway bar needed if you do you have aftermarket LCA and UCA. I have LCA but not UCA, is it okay to take it off?

I don't go to the track often.. maybe 4 or 5 times a year. Any input would be great :)
 
Are you able to tighten it to make the squeak go away? I need to crawl underneath mine, because I think this is what is causing an occasional squeak for me. Can you maybe put nylon washers on it / in between the sway bar and the control arms?