I think they probably didn't think anyone would be able to actually read the paper on film. The resolution of TV screens in the 60s was quite a bit lower than our HD sets today. They would just be able to recognize that it was a newspaper. Many of the things we're pointing out wouldn't have been noticed on a 60s era TV screen.
Have you ever noticed-----In the opening of the "Cow Thief" epp, when Barney, Andy, Fletch, and the Mayor are surveying the area, the window in the house in the background has no window panes in the window. It is a 4 pane window frame yet the breeze is moving the curtains in and out the window.
I figured Ernest T. stopped by to deliver a message.
Closely related to this is the number of years Barney was a deputy. In "Barney's Physical", Season 5, he celebrates 5 years with the "Sheriff's Office". In Season 4, Barney celebrates being sworn in "10 years ago last month".
Sorry if this was already posted!