Religion is a crutch for the weak in the same way that mcdonalds is a crutch for the hungry. Generally, religion supplies two things to its devotees: meaning and morality. The reason these are so important is because they are so hard to find otherwise. If anyone can come up with a good logical argument as to why people should follow a moral code that doesn't neccesarily benefeit that person, I'll be very impressed. Likewise, what would you say if someone asked you, "what am I suppposed to do with my life and what makes my life worthwhile?" Really it all boils down to the pursuit of long life and happiness, not some greater purpose.
So for those who can't invent their own reasons, there's always religion. I know people, seriously depressed, who have turned to religion to give their lives an artificial value. Religion is, unfortunately, a necessary crutch for some people. It allows them to live their lives happily, if not meaningfully.
Personally, I stay away from religion. I value intellectual integrity over happiness.