Why would you buy from 3 or more different stores? I would bet you can find the cheapest or at least the nearly cheapest option in a single store or at most 2 stores. And at least around here stores have free domestic shipping when the price is above a certain point.
As for packages getting "lost" in transit, I'm sorry to hear that you live in a place like that, but that's certainly not true for every country. An alternative might be physically going to the store and picking the items up. For example, in a lot of places, nationwide store chains have the option of getting your online order delivered to a local shop near you where you can pick it up at your convenience.