The "normal way" this is done is by inserting small errors
If your product is hosted on a web server, so all the user can see is the browser rendering, and cannot get e.g. navaid coordinates, then you might get away with using a ripped-off database. But e.g. the plog will reveal them
An amateur can do a lot of stuff but when you get big you can't do that anymore...
Eurocontrol change the structure of their database regularly, to block ripping programs. A friend wrote a ripper for the EAD site, years ago, and it would work for a few months only. In fact they change a token within the URL more often than that (which annoyingly stops bookmarks working pretty quickly). But if you pay some 4 figures for their B2B access, you get access to the database itself.