And it doesn't last very long
Unless you're obsessed with your car enough to spend a few hours every other weekend waxing it, you're not getting anything close to the protection you need. Wax's foils are simple and unavoidable: it's incredibly susceptible to the elements. Even parking in the sun expedites its deterioration.
Ultimately, the one thing real wax does well is add a slightly yellowish depth to the look of your paint -- so if you've just dropped five figures on an absolutely perfect paint job, go right ahead and keep using it. Otherwise, you're doing things the old-fashioned way, which in this case, means more difficult and not as good.