We all do it our own way and what we feel used to and most comfortable with, there's no right or wrong way, and like others I've found some of the posts disrespectful
I don't think it's particularly a religious thing to be honest, I'm not Catholic but adhere to our traditions, its what the family are used to and feel right about .
The wake is a truly comforting thing, its way of celebrating the person's life as their friends and family talk and laugh about their memories, older children are often there if they want to be, and for me it's so useful in bringing it home that death is a part of life and something which is natural and not to be feared. We are all born and we will all die.
The funeral takes place which can be either very religious or have favourite songs and stories, whatever the family feels is right, it's again a celebration of their life and both the wake and funeral are for the living as well as saying goodbye to their loved one.
Grieving goes on during and after that of course.
If you are comfortable either waiting longer and feel it's strange that's fair enough, I would never judge someone else's choice in something so important.