right... but there are different kinds of cotton.... knit and woven refer to the way that the fabric was constructed. Typically if is knit its stretchy. If its woven, its not so stretchy. One example - tee shirts are knit. Jeans are woven. Both are cotton, but handle completely differently.
I haven't started yet, but I am going to make cloth foods for my son using old clothes. I plan on making sunny side up eggs first. Then, probably some fruits and vegetables. I'm just making the pattern up.
You could also cut into squares for cloth wipes. Or, you can use the wipes in your kitchen (just soak some in the cleaning solution of your choice).
I did make a knit hat out of an old t-shirt, because I couldn't find his size in the store. I just used the bottom edge of the t as the "brim" and cut a semi-circle ish shape. No hemming- just sew the top.