They take bribes in the form of local business investment. If you can dump a few hundo k a year into the economy, they’ll let you get away with almost anything
It's slowly beginning to change. They used to fight but they don't care as much about non Emiratis anymore. Even less diplomatically important countries like South Africa have gotten extraditions. Look at Ramon Abbas ("Ray Hushpuppi"). Spent much of his BEC millions in Dubai and still got shipped off to America.