That is why it is important as a seller to make sure your landscaping, curb appeal, front door, are all in pristine condition. The buyers will be standing there looking around while the agent gets the key out of the lockbox. I always make sure that I educate my sellers on this.
As a listing agent, a successful listing agent, there is no way I could be at every listing before it was shown everytime to unlock the door and turn on lights. That is why we have lockboxes All I would be doing is driving around town everyday turning on lights. As a seller, I would not want to work with a listing agent if they had time to do this. You agent should be working for you in many other ways. There may be exceptions to this, but not generally speaking.
Hope this helps, let me know if you have other questions.