Sometimes, the the title of a post doesn't quite describe what the post is all about. I think this post is a classic case of the above.
I'll try to keep it as simple as possible.
Suppose you are writing a program to compute the factorial of a number, you would also add a function to find if a string is a substring of another string, or check if a string is a palindrome? If you answer "yes" to any of the above questions, I would surely like to see you actively use the above in your program. For the rest of you un-interesting lot(Rule:0 of blogging; never lower the self-esteem of your readers), I would like to ask you if you would eat a packet of biscuits just because it was available for free. I'm guessing you wouldn't eat anything unless you were hungry, and if you consider biscuits as not belonging to the class of "healthy foods", you probably wouldn't eat those as well.