I suppose it's like any business decision - you weigh up the pros and cons, look at what your USP is (if you have one), write up the business plan and see whether or not it's viable.
At this stage, there are few barriers to entry, and the real killer is likely to be overhead costs, if you're looking at bricks and mortar. There would seem to be a few "businesses" trying to find a USP that, to many on here, seems like usury and profiteering (no names, no pack drill, but let's say "subscription"), while, it seems, the assembled throng would like businesses to make very little money on each transaction.
That is what will, in the final analysis, determine whether or not you will succeed. In a market that is price-driven, the only winner is the manufacturer, as he can produce to a price or stop production should downward pressure make it unprofitable. Ultimately, customer service and quality of product suffers.
Someone, earlier, mentioned expensive watches. I don't see Rolex or Patek Philipe posting massive losses!
Seriously, a local supply chain has numerous advantages over Web-based commerce, not least of which is immediacy of delivery and personal contact. I will, however, admit my bias here - I much prefer to buy locally whenever I can, rather than facelessly over the Web, in order to support local businesses, and I have an in-built distaste for businesses which set out to destroy other businesses by simply undercutting them out of existence.
Good luck with your determinations, and I truly hope that you can find a model that will work for you and your customers.