Well, there are two problems then. First is to identify the product, and second to build a database with all the information you want in it. Google Goggles is one attempt at identifying "things" based on their appearance (or rather, the picture's similarity to other images in its vast image-search database); we'll need to wait for that sort of image recognition software to mature before being able to use it effectively.
The second, as mdwh says, is a massive project. You'd either need the government to do it, or to crowd-source the solution. For example, many people use websites that give you nutritional information on products. I've used Fat Secret in the past:
http://fatsecret.com/ . Users can scan the barcode or search the database manually to find the product they're eating. If the product isn't there, they can tap the numbers in themselves, based on the legally required nutritional information thing on the packet (or based on whatever information they have). That way, the users build up the database themselves, which is a lot cheaper and quicker than having one company go out and find all the nutritional information for all the products themselves. It's kind of like wikipedia, only for nutritional information. Of course, it requires a critical mass of users to work, but that's a matter of marketing, not programming. There's no reason why you couldn't make a website that did the same thing that Fat Secret does, except for the kind of yuppie information you're after.
But anyway, neither of those things are "apps", they're just giant databases. As mdwh said, the app part is trivial once you have the database - it's the database that's the hard part. But I mean, there's no reason why you couldn't hire a web developer to make the website for you, and then sell ads on the site to turn a profit. In otherwords, you're not describing an app, you're describing a web start-up.