"Roog" by Philip K. Dick

First appeared in F&SF. Reprinted by Anthony Boucher, J. Francis McComas,  Robert Silverberg, John M. Landsberg, Jonathan Ostrowsky-Lantz, Jack Dann, Gardner Dozois, Stefan Dziemianowicz, Martin H. Greenberg, Robert Weinberg.

This was Philip K. Dick's first accepted story, but not his first published. It tells of a dog who can see aliens as garbage men.

Discussion (with minor spoilers):

While not a classic, this is utterly charming. Part of it is the perfect name for the alien which sounds a bit like how a dog might sound, barking.

What's fascinating is a debate with the famed editor Judith Merrill over the story (a debate which you cam read about over here). She thought that the description of the aliens did not match the garbage-men she'd seen. This is the kind of debate that sidetracks a lot of literal-minded fans and editors and critics. Myself included. 

Even Dick is mostly persuaded by Merrill's argument that he have lost sight of his own story. He calls it a fantasy through the dog's point of view. It could be. A realistic tale of a dog who thinks garbage men are aliens. But there are other possibilities--more interesting ones.

That's the key: Whose POV is it? It's probably not the dog's. Maybe, but probably not. Was the dog there to witness all events? Maybe? Certainly not the humans--at least not these humans since they don't seem to know what's going on (perhaps humans in a post-human-Earth era?). Maybe the aliens, but they don't seem to be there to witness everything as well.

Perhaps it is simply an omniscient narrator. The aliens, if real, admit what they're doing. They're making the dogs or Guardians seem like deluded creatures. Maybe they are. 

Or maybe the aliens are deluded into thinking the dog see them. Maybe the dogs don't see the aliens as aliens at all.

But again maybe the dogs do. Maybe they are masked and dogs can see through the disguise.

What the aliens are up to, isn't clear. Are they just after trash? Why is it an "offering urn" and why do they eat it? Do they consider themselves gods? Or do they offer it to other gods, carrying it in a blanket? Whatever is going on, it sounds sinister. And once they clear out the dogs, they will be able to execute that plan.