Well, I buy things all the time online for the dogs. I have to buy all my dog sledding equipment online. The nearest dogsledding equipment "store" is well over 12 hours away.
I buy all my vet supplies online. They also have things on there like toys, treats, beds, leashes, most of the things you'd find at a place like Petco (plus some!) If your dog even needs a prescription, they can fill it, and mail it out. (Probably cheaper then the vet!)
They also have a "naturals" store for the humans, and equine and livestock store. If you want to check it out, its
www.valleyvet.com