instagram could be used in promoting business, as social media sites play a vital role in promotion of business so one can take picture of his/her product and upload it. Other people could also be used for this purpose, for example if someone is running a fast food restaurant or pizza place owner can offer a deal that the person who takes & uploads the best picture of their product, his/her name along with the picture will be 'picture of the day'. This will help in marketting as well.
Plus now that Facebook owns instagram that's another 900 million people a small business can be exposed to if they do integrate. It sounds like a win win for a small business if they'd do something like that.
There's definitely a use for instagram in many types of small business! Jessica said everything on my mind; I've seen businesses do just that. The aesthetic of instragram photos is really appealing and if I see a picture of a delicious sandwich, I would totally be inclined to ask where it came from!