I think people are trained to respond to everything, even if its a quick note to say thank you. This is especially the case if its a personal sounding email fr

I think people are trained to respond to everything, even if its a quick note to say thank you. This is especially the case if its a personal sounding email from someone important. After that its just a matter of forgetting to pay attention to the address bar before hitting reply, possibly with a shortcut but more likely just going on autopilot and clicking things.