For the record, Sheriff Smith has a very pro gun record. I have met him and have a great deal of respect for him. As a firefighter and resident affected by the High Park Fire, he did a fantastic job helping us out this summer. He also actively encourages CCW. I do not know where he stands on open carry, but he earns my respect as a good guy.
As for the other Sheriff's that do what you are suggesting: It often seems to be more of a publicity stunt than anything else.