While coloring pages may seem simple in the minds of parents and other adults these days, they are often the passport into a more creative style of play. Yes, your child will simply color the picture online, but by doing so, she is learning not only to stay inside the lines, but to balance color and texture and to simply use her imagination. If a coloring page for kids is the first step into a full-fledged imagination based entertainment package, it is unlikely many parents will find them simple for long.
Being an understanding and caring parent, you can help you child in learning about various things and in creating awareness in the child about the world that he/she lives in with the help of coloring pages. You can use these pages for developing the ability to think logically in your child in a simple way without making learning a boring process for him/her.
With online printable coloring pages you never have to keep volumes of coloring books around. Most children change what they would like to color often. They bounce around from one theme or one set of characters to the next. Therefore they may abandon that coloring book with princesses or cars days after you buy it. Printing out the pages though allows them to always get what they want.