Before this psalm closes, there are a few words to the wicked. That term refers to people who refuse to turn their live over to God. This verse is here almost as if someone is thinking, "OK God I know I am committed to You, but what about that person over there who never does anything."
I don't think these verses are for the non-committed as they don't read the psalms. They are for the believer to understand what happens to those who are just going through the motions of going to church but never really do much about their trust.
One example could be the businessman who only goes to church because it is good for business. Another example is the adult parent who merely goes to church because they want their children exposed to religious people.
These are the type of people God is addressing in these verses. They go through the motions and recite along with a memorized prayer or a song, but their hearts don't really care for the things of God. Let's be careful not to be a people who only give lip service to the Lord while all along disobeying Him in our lives.