There isn't anything weird and the Repeater works exactly as it is meant to be working. You are just not putting in enough effort to get the effect you want by isolating transforms. You simply need more groups. You put the animated rectangle in a group and make it move from left or right, then you repeat the entire group by putting it inside another group and applying the Repeater for the radial array cloning.
this solution works for me but i can not understand. all tutorials on the web do it without creating a group. i also did the same. but one day it started doing so,i have copied old layers and tried to change,but no, still the same. if i change content of that layer,repeater starts misfunctioning. i think this is a ae bug.
my other solution was binding repeater anchor to minus elipse or shape position value with an expression.