Pistons don't redirect redstone correctly

This glitch basically entails that redstone dust doesn't redirect power how it should when next to a piston/sticky piston.

 

This bug can be reproduced by placing a line of redstone wire, and placing a block that needs power at the end. Then place a piston next to the redstone dust adjacent to the redstone component.

 

What I expected to happen:

The redstone dust should either property display that it is powering the piston and redstone component; or that the redstone lamp dhoush not receive power.

 

What happened:

The redstone dust redirected only to the piston, despite it still giving power to the component.