Do most players use hacked Pokemon?

[Planb900]

Hey guys,

I've been playing Pokemon super casually ever since LeafGreen, but as of a few weeks ago I decided I wanted to start playing competitively online. Recently in Omega Ruby I've just been catching and breeding and preparing to create a team for WiFi battles, but I just had a question; do most players catch their Pokemon and breed them like I do, or do people generally just hack perfect IV Pokemon into the game and play with those? Is that even allowed online?

Thanks!

-Tate