"Sprinkled throughout in dialog" sounds quite wrong, since everyone in the wasteland cussing time to time would be awkward. But I think I shouldn't take it literally.
Anyway, people do cuss. So if there's no cussing at all in the game it'd be unnatural. That being said I'm okay with any level of cussing as long as there is some. A nice believable RPG can be made without using strong language (Planescape: Torment) but there's tends to be some potential wasted in my opinion. Strong language also creates some opportunities for humor. It's wasteland and I think there bound be some people in the wasteland that are offensive, and has foul mouth.
Renesco in Fallout 2 is a well-educated, intelligent fellow and utilizes a impressive vocabulary yet he's so mean and misanthropic. See his dialogue file here: http://fallout.wikia.com/wiki/NcRenesc.msg
He uses strong language but that doesn't make him less believable, in fact I think he's a very strong and well-constructed character. He can make you feel like a idiotic loser when talking to you. He doesn't actually use the words "fuck" or "shit" but it still is a good example for showing how strong language can be a important component for a character.
Also I assume there will be some thugs or bandits in the world of wasteland (I'm not totally familiar with Wasteland universe so I'm just guessing), it'd be weird if they talk nicely.
Also playable character should have complete freedom in his dialogue options. I'm not saying that I necessarily want to insult anybody in the game, but if someone pisses me off, I at least want to be able to be rude towards them. Another example from Fallout 2 on this:
What Jules says:
• Your CAR? You sure you parked it here? I ain't seen it.
• What, you suddenly gone BLIND? You see my FIST, mother fucker? You SEE it?!! Now tell me again you haven't seen my car'I fucking DARE you.
• Jules, if you don't tell me what happened to my car, I'll tell Family Wright YOU sold their son the Jet that killed him. You'll be dead within the hour. Talk.
• You SURE you haven't seen it, Jules?
• Yes, I'm SURE I parked it here. Any idea where it might be?
• All right then. I had some other questions'
• I better go look for it.
I think most people agrees on there's nothing wrong with cussing as long as dialogues crafted in a realistic and believable in the game's setting. People in nice small settlements would be talking nicely and would be apologizing for their involuntary derogatory remarks. Where's that wouldn't be the case in a poor town that's run by bandits and such. It's important that cuss words shouldn't randomly be distributed among all characters but there should be people who doesn't necessarily talk nicely.