Attacking the minions needlessly can screw up lane position which can put your ADC in a bad spot. If your ADC is recalling and the minion wave is trapped on their side, it wouldn't hurt to push it under the turret completely for them so it will reset; however, if you're just pushing regardless when they're not there, that can leave the wave over extended and leave them vulnerable to all in's or jungle ganks. This is especially bad if the enemy support is a heavy all in champion like Ali or Leo who can pray on the ADC more easily if they're over extended in the lane. That said, you shouldn't AA the minions unless you're trying to help them push after killing them. AA'ing the minions can throw off your ADC's last hitting which is frustrating for many of them.