Carry Kills vs Support Kills

It's not that big of a deal, the Core still gets an assist, and if no other enemies are in that Lane, Free Farm along with it.

Persoanlly, I am more of the opinion that the Kill priority should go to:

Anyone who nearly has a major Item->Gankers who need/really want to snowball->Supports->Junglers->People Farming a Lane.

If your Position 5 Lion is 350 Gold away from getting his Blink Dagger, a single Kill suddenly beomces huge. If it goes to a Troll Warlord who's only just finished Farming a Black King Bar and is nowhere near his next Item...have you really gained that much from the Kill? This only applies at certain times, but the only thing better than getting a big Item out of a Kill is getting Rax/Throne out of it.

If you're playing with a Hero like Slark, they should take the Kills the rest of the time, they need it get ahead as Gankers make poor Farmers and will have less of an impact with less Kills.

If you have no Gankers and no one is close to a big Item, give it to the Support. Securing some xtra Gold may mean they can get a small Item such as a Bracer to improve their survivability/effectiveness in fights. A Kill for the Core just doesn't have the same effect as they'll usually get Free Farm from the space created.

When playing, usually you want to give supports a few early kills to put them ahead for a Mek in Blink Dagger. Then Carrys get the kills mostly. But not at all costs. Do what you have to do to get the kill with the least amount of deaths.