The Golden Bugs

Story, first published: The Magazine of Fantasy and Science Fiction, June 1960

"The Golden Bugs" are aliens with a hive mind who invade suburbia and greedily gobble up all the metal in the neighborhood. The suburbanites drive off the invaders with ultrasonic waves, but even after the alien menace has been eliminated, the protagonist is torn with doubts if he has done the right thing. "... The first things from space had come and we had smashed them flat... Would the driving sense of fear and the unwillingness to understand bar all things from the stars?"

Ewald, Robert J.: When the Fires Burn High and the Wind is from the North, p.58

Alien little buggers, who turn out to be quite helpful actually... at first. They clean the household, do the lawn etc. But then the trademarked Simak weirdness begins, unfolding on a perfectly normal "american suburbia" background. With such a subversive, sublime approach Simak seems close to Philip K. Dick's style (whose mental plot structures are far more vicious than the mere "sense-of-wonder" vehicles of Simak's). You never know what may jump at you from a perfectly normal cup of coffee. The only difference is, in Dick's case it will be an agent of different reality telling you that either your reality is toast or you live in a soup yourself, but in Simak's case it will be a cute, but properly weird, well-meaning alien who does not want to disturb your breakfast, but...

Abrams, Avi: Science Fiction and Fantasy Reading Experience: Clifford D. Simak