First I would say that as the value goes up the eBay sales go down. I could be wrong there, but I'd think that most people buying cameras are "tire kickers" and would like to hold them in their hands and have a place to return to if there are problems.
Second, the high street stores in general do not pay a lot of attention to eBay. You may see it as a real battleground, but there are still way more people who buy in person or from trusted brand websites than do on eBay. And most real retailers hold their prices the same in-store or on the net.
I was years in business in a regional mall and never sold below suggested retail and often bumped it up a bit over. There was not a week go by I didn't hear a comment about "Oh, you can find that cheaper on ebay." But they kept buying and I kept my prices just where they were.
If someone wanted to haggle, I'd just tell them "Don't buy it. Whether you buy it or not I know for a fact that by 6 PM on Christmas Eve it's going to be sold at the price it's marked. I can tell you right now that by the time we close on Christmas Eve you will be able to count the remaining items on your fingers. If you don't buy it someone else will."
With so many hoping to make their fortune on eBay, I hate to say that it's not the only place to make money. In fact, it's falling off, not growing at all like it used to be.
Smart retailers pay it absolutely no mind whatsoever.
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