Well, when I right-click the page in the viewer and select AutoLevels, I get a line:
Levels = x,y
However, I placed the cursor just below this line:
Pages = all
So naturally the Levels command applies to all pages, which isn't desired because of the reasons you state. However, the instructions for AutoLevels in Tools hints that if you right-click a page in the viewer, the Levels command generated will apply only to that page, because "this command will perform the autolevel on each page" (emphasis mine).
The expected behavior would be that if you right-click on the page in the viewer and select AutoLevels, you will get a line that only applies to that one page. In other words, I think the behavior when you right-click on a page in the viewer is to add two lines, the first being a Pages command which selects just that one page, and the next being the Levels command.
I hope that makes sense.