Rubber Bands for Securing Packages
Instead of clips, use rubber bands for securing opened plastic bags. These are cheap and usually don't break or come apart like clips can.
If you buy the big multi-pack of rubber bands, there's a size for every need. As you can see from the photo, they work great for securing everything from tiny packages of nuts to medium-sized packages of toffee or chocolate chips to larger things like baking mix and cereal. I usually just slip the baking mix back into its original box with the rubber band securing it. For cereal, I usually just toss the box and store the cereal in its plastic bag with the rubber band around it to save cabinet space.
I have been doing this for years. I think I just got tired of looking for clip or having the clips break.