RangeSlider stepSize property does not appear to work

Setting the stepSize property of a RangeSlider does not appear to affect the values produced. When printing out the left and right values of the RangeSlider, it always produces some decimal value even when setting the stepSize to 1. I tested the same thing using the normal Slider, and the Slider functions as expected. 

Please see the attached example which clearly demonstrates the behavior I am seeing.