I don't know about Wal-Mart, but every other site you listed is famous for being filled with Chinese companies that make cheap knockoff garbage. Yes, even Amazon. It's like the perfect blend of enshitification and consumerism.

I don't know about the tech companies, but with clothing companies you'll see the exact same companies with names like asdfghjkl on both Amazon and Temu, selling the exact same product with the exact same pictures as 3 other similarly named companies. And what you buy will only last slightly longer than the 6 months the company is around for before it disappears and the owners open back up under a new name.

For tech, you gotta do research and see what the experts are saying and find out the reputation of the brands that you're looking at. Unfortunately, it isn't as easy as just going on the website and checking the reviews.

As for your original question, I think the answer will be FOSS projects. No company is going to willingly drop the potential ad revenue of AR ads. "This dream brought to you by Underwear brand briefs!"