Makes you look really successful (they pay a lot, so they must be super profitable!) and helps, at least partially, select employees who won’t be asking questions, just do their job and collect paychecks.
If I sell you a book on how to be succesful, and am not succesful, I have to fake success to get you to buy. So maybe I'll rent a sports car, overspend on my rent, go to holidays I can't afford, etc. because enough people might be fooled to allow me to actually afford these things.
Tons of "financial influencers" have constant videos of them with lambos and other expensive toys. It's basically the same thing - image is everything in speculative parts of the financial market.
High salaries makes people want to work there which creates competition which in turn drives prestige.
Not asking questions is a little facetious, however it is plausible that things like questionable business practices are easier to overlook when working / applying for a job because $$$. In other words, it's very hard to explain a concept to someone if his livelihood depends on him not understanding it.
"It is difficult to get a man to understand something, when his salary depends on his not understanding it." is not a quote I've invented. Now apply that to getting way above the market salary.
Yes, most of the people don't question how ethical their jobs are. But you make them even less likely to do that if you throw money at them.
Makes you look really successful (they pay a lot, so they must be super profitable!) and helps, at least partially, select employees who won’t be asking questions, just do their job and collect paychecks.