Block for 2 reasons, bareshaft tuning and broadheads.
I have several bags and several block style targets. I shoot the block targets 90% of the time. I get less arrow damage in block targets when shooting groups because the arrows stay straight and don't kick to the side leaving the side of the arrow exposed. .
I know I know..."don't shoot at the same spot"!
I like to shoot at the same spot at 40+ yards. It just feels good to see the arrows in a tight group at longer distance.