There are two theories. One is the King plastic spacer is not up to the job. I use the aftermarket AGM sliders and don't have a problem with noise and the springs sit straight. But those are expensive and many (most?) say not necessary. I never ran with the King slider so I can't say.
The second is they will break in and go back straight. What makes them cocked is the spring-aluminum interface at the top and bottom, and the two slider-spring interfaces in the middle. If just one of those spring end faces is not completely flat (or if the plastic spacer isn't molded just right) it will send the spring off on an angle. That interface really "should" wear flat with use.
The AGM slider is longer, so it forces the springs to stay straight.
Dave
I work for a company that designs and builds Nightvision binoculars and several other products closely related. We have the tools to make some of these sliders but I'm curious as to what material they are made of. We use a hard plastic called Delrin . I wonder if that would work?