You certainly don't have to have the make your tote bags so that they can close. I am a such a klutz so being able to close my tote bag is important to me and when I give them as gifts, it does make it look impressive especially to non-sewers. Buttons are another love of my life so it's nice to be able to use them.
I know a lot of people fear making button holes, but sewing machines make it really easy. Just follow the instructions in your sewing machine manual, it usually just five easy steps. I usually make the piece match both size and color of the piece of fabric (you can see it in the Tote Bag Crazy post but this time I wanted to see what it looked like a little bigger. Just remember to make it work for you! There are no rules.
If making button holes just isn't your cup of tea, then try option two. There are all kinds of fabulous fibers and cords available to use or you could even make your own! I usually cut the cord around nine inches making sure that an inch is in the seam. Stitching around the edge of the bag provides not only a nice finish and provides extra security. Enjoy!