Descriptions in writing and roleplaying, from my perspective, can be used not only to set the scene, but to determine the tone of the work. Are you trying to use the "background" as a commentary... in other words, are the dark skies, pouring rain, cold, rocks and mud all to set a somber mood, your character caught in this storm depressed and sad, perhaps simply "desperate" to get somewhere warm and dry? Or are you setting a contrast? Is your character cheerfully splashing in the puddles, ignoring the cold and mud?
Well, this tends to be the way I look at it. No, I'm not always concerned with the point, because sometimes a "cigar" is just a cigar. But there are times when "Realism" in describing a setting can indeed fit into the intended tone, or the "theme" of your story. Heh... in roleplaying, however, quite frequently you have to deal with the pre-made setting, so, you have the choice to ignore "meaning" or to take what's presented and, through your character descriptions and interactions, turning that meaningless background into something with significance to your desired theme.
Want to use a "serious" description seriously? Have at it. Want to take that and flip the tone? Take that serious description and find the contrast or humor in it... make your character dance with the thunder and lightning. Or simply drop a "banana peel" on the ground. And have your character slip on it. So to speak. Though to be truly honest, personally, I don't stress it. I simply write in a way that pleases me, be that Realism or Surrealism or... who knows?
Everything doesn't always need to make a point, because "pointlessness" could very well be your point, right? Variety is the "spice of life." And all that.