If your model of big business is that it's a tool for exploiting workers, you'd expect the opposite of this dynamic. Instead the economics is pretty clear that most large firms create synergies that empower individual workers to produce much more than they'd be capable of individually or in small, informal organizations. As a bonus, the sizable bulk of this productivity surplus accumulates in the form of higher wages to the workers themselves.
Big business accomplishes this by consistently applying the best practices in organizational management[2]. In contrast small business tends to be much more sloppily managed with a lot more decisions made haphazardly, with many more decisions being made for individual gain rather than the good of the organization as a whole.
If anything the balance of the evidence would make a much stronger case that small business is really more exploitative than big business.
[1] https://www.jstor.org/stable/117089?seq=1 [2] https://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.24.1.203
What I'm guessing you're referring to is median household income. Which is a quite different number than mean worker income. The former has stagnated relative to the latter primarily because a massive number of prime-aged workers, in particular young men, have dropped out of the labor pool.[3]
Why that's happened is an entire question all on its own. But one thing is clear, the reason for it certainly can't be big businesses exploiting labor, because by definition the unemployed aren't working for anybody at all.
[1] https://www.statista.com/statistics/243846/total-compensatio... [2] https://www.bls.gov/opub/btn/volume-6/below-trend-the-us-pro... [3] https://www.bls.gov/opub/mlr/2016/article/pdf/labor-force-pa...
https://www.pewresearch.org/fact-tank/2018/08/07/for-most-us...
Mean wages have closely tracked productivity metrics. Median wages have fallen relative to mean wages. That strongly implies that the issue isn't decoupling between wages and productivity, but faster growth in the output of high-skilled workers relative to low-skilled workers.
This is confirmed by the empirical research[1], which shows that 61% of the divergence between median wages and productivity has come from income inequality between workers. Only 25% has come from rising corporate profits.
[1]https://www.epi.org/publication/ib330-productivity-vs-compen...
Does rent seeking count as productivity?
This is how it works with idealized new products. With highly competitive fields it is more zero sum, in that you take some pie from your competitors. But that's still good overall as it's adding value and making the market more efficient.
The only true zero sum game is the market for attention and why I despise social media companies. Everybody has a fixed amount of time, you can only grow that pie by adding more people.
If I provide enough value to buy a thousand lifetimes worth of food and sit in my castle with it while people outside my moat starve - am I not selfishly hoarding that food?
One has to balance harvesting eggs com the golden goose with not killing it or driving it away.
Taxing just billionaires specifically wouldn't do much as there aren't many of them. It would have to be a broader tax of some variety.
Billionares could be taxed more as a penalty of parking their money in a safe fiscal heaven and it is very doable if a concerted effort is made.
Certainly not all physical stores are unnecessary, but it may not be the case that society is better served by brick and mortar stores than Amazon (and similar), despite lost jobs and (temporarily) abandoned commercial space. It may just be progress moving forward.