Question: What do people do who don't save at least a few newspaper rubber bands or a generic plastic bag or a pretty piece of paper now and then?
Answer: They go out and buy them or their equivalent when they need them.
I remember my Mom talking about my sister in law who came to her for rubber bands and plastic bags because she threw hers out (over and over and over).
If you save all those things you think about, you'll never lack for something to fasten things together, something to put things in, something to mix a little something in, something to decorate something with...
If you're going to hoard, do it in an organized way by having a particular place for each item or type of item. Boxes, both large and small, come in handy for this, as do drawers and less frugal organizers and you can find what you need faster.
And a word of advice: If you're not going to hoard... get to be good friends with someone who does. Who knows when you're going to need a cone shaped piece of cardboard (that cotton yarn came on)?