(Only responding because you were downvoted.) I also would not generally call "fast food" "restaurants". When I read the title, I was thinking "huh, what ads? ones at the restaurant itself? the ludicrous websites restaurants tend to? but aren't those usually only showing shots of the interior and not the food?" and then I realized "oh, they mean fast food". I certainly eat at places like Subway and Taco Bell all too often, but it sounds wrong to me (in the cultural linguistic context that I have) to then say "I went to a restaurant today", I'd have to say "I got fast food" or something.