Terminal app can access folders that it isn't allowed
My first question is: why would you do that to your terminal.app?
To answer your question. Terminal.app is automatically granted Full Disk Access by default and it does not show up in the Full Disk Access tab on the Security Pane.
You can see this by running the following in your term:
sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db 'select * from access'
I hope it answers your question.