But the perception I'm talking about applies even to "reasonably confortable" people. Think your random engineer making 100k a year (which is a "good" salary in these parts). Basically, someone with some form of STEM degree.
I doubt most of these people are doing anything shady. Plus, this kind of income doesn't really give them any kind of financial independence: they wouldn't be able to afford not having a job.
I guess it depends what your level of "shady" is - I know a bunch of people in that kind of range who were all about "optimising their tax" (which I would consider to be "tax evasion" - morally wrong even if it is legal at the time.)
For example: France offers specific saving deposits with guaranteed interest rate and non-taxed. If a normal saving deposit would be taxed and has similar interest rate, "optimizing their tax" means just using the that specific deposit.
There are many other schemes that I can't believe they exist (example: in France if you create an investment account, after 5 years of the account existence you are not taxed on the gains! So what you can do is "create account with 100 euro", "wait 5 years", "invest more / potentially do gains" - and you will not be taxed!!!)
You will tell me "that is morally wrong!". I could agree with you, but I see nobody demanding better laws/regulations, probably because they don't know/care about details.