Yes, it 100% absolutely should be. There is absolutely -0- excuse for a support, no matter what his champion is, to start taking CS from the ADC. Even if the ADC misses every last hit on planet earth, there is no excuse under the sun for a support to start taking cs during lane phase. I -ALWAYS- report this.
I am a main support player who recently started playing a lot of ADC, and I speak from experience when I say that: you have no business being a support, or queuing as a support, or even queuing "fill" with a chance at being a support, if you are not willing to find another way to generate gold revenue, zone properly, heal, ward, shield, CC and do everything in your power to ensure your ADC has an optimal chance to farm and last hit.
Support is the most important position in the game, and if you're going to fuck it up that badly, you deserve to have every punishment available under the sun cast upon you.