Amazon has my sister's address information already saved, I can just click it from the list when I'm buying presents for my nephews.
Brands still have value when properly managed, don't let anyone tell you they don't.
If everyone behaved like you, requiring a 40% discount before moving away from Amazon, then Amazon would just set its prices 1/.6 = 66% higher than the other stores. Fortunately, not everyone is like you, so Amazon's prices are often competitive.
To some degree, I suppose this is like buying index funds versus buying individual stocks. I only buy index funds. But the reason I can get away with it is that there are at least a few people out there searching for value. I can't compete with them. But I can price-compare online, or at gas stations, etc. I see shopping for low prices as part of my duty as a capitalist. :)
The term "price sensitive" is a bit misleading. A better term would be "value sensitive". Your duty as a free market participant (I prefer that term because "free market" is not necessarily the same as "capitalism") is to get the best value you can for your money. But that is value to you, and will be different for different people. Also, that value has to include the cost of the time and effort you spend searching for value, which is also different for different people.
> then Amazon would just set its prices 1/.6 = 66% higher than the other stores.
And such would be the price of convenience.
I shop at Publix and pay the higher prices over Kroger because Publix is 5 minutes away from my house whereas Kroger is 10. I don't do major grocery shopping as I'm single. I'm happy Publix exists and if everybody were so price sensitive they'd drive to Kroger instead, Publix would go out of business or lower the quality of their services so they can compete price-wise with Kroger.
Having multiple store options available diversifies not just the market for goods, but also the market for shopping experiences. Price-sensitive shopping, if everyone did it, would absolutely lower prices for everyone, but ultimately would reduce options. I would hate to live in that world.
I bet that Kroger has a better, more convenient experience than it would if Publix wasn't there, simply because Publix is an option. Kroger does have self-checkout lanes and nice decor, just not as nice as Publix's.
I've been surprised the extent to which Amazon's achieved voluntary lock-in for me. Amazon's good-enough in my spot-check price comparisons, and instantaneous with zero marginal-cost shipping, that they're now my default place to search for many products.
Find a niche to live in. Taking on Amazon directly is probably trouble.
I also don't buy big-ticket items lightly. If saving hundreds is a possibility, then there are also way way more considerations, and I'll probably end up targeting a particular model of a particular brand, then I'll search for the best price. Your solution may work for that, but so does Google and just going to each retailer's website manually.
With big ticket purchases, convenience isn't really a factor in my purchase decision. To me your product is a solution in search of a problem. I hope I'm wrong.
It scares me a little bit that nobody is even trying to compete with Amazon. When somebody does do a better job at something than Amazon, it seems like Amazon just acquires them (Zappos, for example).