I would call these databases complementary, not "entirely superior". There are two main advantages. One is that these databases will contain many things that you can't find on Google. The second advantage of these databases is that they are designed for advanced searchers and have more powerful query languages. Google on the other hand is dumbed down and will try to guess what you want, often doing a poor job. You can get very specific on these databases in ways that you can't with Google.
Related: I'm somewhat fascinated by more specialized bibliographic databases because they often contain things that can't be found on Google or the major commercial databases I listed above. I started keeping a list of them. https://github.com/btrettel/specialized-bibs
This is the big problem with this "trick of the trade". It's not a trick, it's gatekeeping that excludes anyone without a university affiliation.