I think all of us live with a certain level of OCD, we just differ in what we obsess about. I also don't think we necessarily choose what it is we obsess about...it just happens. I have well documented food touching issues, so now add to that some scent issues:
1. I don't think your hands should smell like mint after you wash them. We received some peppermint scented soap from a neighbor for Christmas, the fact that it is still around 2+ months later is a testament to the fact that it doesn't get used really often. If the other soap dispenser needs refilling and we are all too lazy to be the one who actually refills it, the peppermint soap gets pulled out. But I am oddly unsettled when my hands smell minty fresh.
2. Your breath shouldn't smell like bubblegum after you brush your teeth. I am well aware that toothpaste manufacturers make odd flavored/scented toothpaste to encourage children to brush their teeth, but it is just wrong. Bubblegum is not a fresh breath scent.
3. I love my Scentsy candle waxy smelly thingy, but I turn it off if I am baking something aromatic. The smell of fresh bread combined with the scent of melon...or flowers...or whatever is wrong.
4. This last one isn't necessarily a smell issue as a naming of the smell issue. We are oddly attracted to paint with food names (pistachio, caramel, lemon), but I hate it when soaps and candles have names like Oriental garden, or spa fresh, spring rain, Mediterranean breeze...you get the idea. Things that you really don't know what they smell like (the only Mediterranean breeze I can clearly recall from my childhood memories of Greece, is smelly body odor). If I can't smell something when I buy it (sealed bottles etc) I want to have at least a general idea of what it should smell like. I don't want my freshly washed face to smell like men's deodorant.
So, to summarize, fresh breath should smell minty, clean hands should smell soapy, my olfactory sensors should not be assaulted by too many scents at once, and products should be clearly titled as to what they are going to smell like.