I can offer some insight into the other side of the equation in terms of Aliexpress, as I've helped some businesses sell products there. You have to keep in mind most electronics shops are racing to the bottom. There are a few problems with Aliexpress as I see it:
Thanks for the great insight! It was clear to me that the sellers don't make much money, but I didn't know it's just cents. Is that also the reason for 5W LED lamps sold as 10W? Sorry, if I'm making fun of it and calling it the Chinese Watts or Amperes. Usually a factor of 2 up to 3 works fine, e.g. if the seller claims the PSU is 1A at 5V a measurement shows 0.5A. The same goes for most products. Recently I bought a 7W LED lamp from a German seller in Amazon's marketplace and the lamp draws just 4.3W.
Many factories will ask OEMs if they want to write fake information on the product to make it more attractive. It's seen as a feature, and so many people do it that a certain percentage of buyers assume that EVERYONE does it.
Shoppers for the most part seem to fall into two camps:
Camp 1 - those who assume specifications are genuine.
Camp 2 - Those who assume everyone inflates their numbers, and so look for products spec'd a bit higher than what they need.
Camp 1 will choose the product with the higher specs every time within their price range, so long as it's not ridiculously astronomical (200000mAh wallet sized power bank for example). Camp 2 will often choose those with higher specs also, because not only are "10w" lights listed at just above the price of a 5w light more exciting to click on and browse, but a better choice if you choose not to trust anybody. After all, you could get a 1w bulb if you shop for 5w.
Let's also mention that camp 1 has been giving those dishonest shops more business and making them appear more reputable and visible as a result as well. Some would assume buyers will know when you're being genuine or not, but that's not usually the case.
I wish people would start leaving negative reviews on shops who use clearly fake specifications. Until shops are punished for listing fake specs, few people will volunteer to do more work verifying the actual product information from the source, and make less money while competitors also are listing the same product with better specs.
That's just my opinion/experience anyway.