PMP3162: GND connection

Part Number: PMP3162

Tool/software:

Dear team,

Can I know the reason why PMP3162 uses common GND for PGND and GND while UCC2897A-EVM uses separate GND and connected each other with 1 point connection.

I believe EVM's example should be generally recommended and not really sure why PMP3162 uses the layout like this. I suspect it was just not considered the noise loop when it was designed.... Thank you. 

Best regards,
Yuto