#1 It's a time tested formula for results
Let's face it. The current incarnation of WWE was built on McMahon family drama. Bringing a superstar's family into the picture allows one to pull back the curtain on what is popularly known as kayfabe. It gives us an insight into their world and becomes an additional layer for fans.
Let's consider the AJ Styles vs. Samoa Joe feud from SmackDown Live, over the WWE Championship that the crowd was into. Samoa Joe terrorised AJ Styles' wife and actually made fans uncomfortable with his malice and his creepy demeanour. Bringing The Miz's father into the Shane McMahon feud allowed the very unpopular heel to go babyface.
Bringing a Superstar's family into a feud is just a time tested method and WWE often goes back to the well with what they know. Drew McIntyre just did what he was told.
And you know what? I'm quite intrigued.
Major rumor about recently released stars HERE