I think your tube idea could work. Since I don't use a knitting machine and don't really understand how they work, I don't know the details of how you will do it. If you think hats and scarves are worthless, then for you I suppose they are. I like making hats and scarves, I also like making other things. Maybe you should make yourself a blanket of lots of different colors. You could use one color till it's all gone and then add another till it's all gone and just keep on going until you get it as long as you want. If it's not wide enough, make more than one piece and seam them together.
We want to help you as much as we can but we knit by hand and that's different from using a machine. We can only guess and make assumptions. When we've tried to answer your question and you post it again and use ALL CAPS we feel like you're SCREAMING at us. Using all caps is poor etiquette.
I did some searching and this site says it has free knitting machine patterns. You might look and see if it has something you can use.
Good luck with your knitting.