Well tubes are pretty expendable to me since I do get them so cheap. So typically I don't patch them. I find old tube more useful to cut up into long strips and use them to hold furniture and stuff I build together as the glue dries. For many of those situations, more effective than clamps as odd angles can be handled easier. And many other uses too from simply tying bags shut to using the loop of an entire tube to wrap around something to hang on a hook on the garage wall. So often I'm short of old tubes when I need them since I really don't flat that often.
You can scold me for not using my LBS. But there are plenty of four dollar or less tubes still available online. I got mine from Walmart. Granted they aren't $4.00 anymore and maybe not the last time I bought them either, which was three years ago when I bought a half dozen or so.
https://www.walmart.com/ip/Bell-Stan...5-32c/34038251
https://www.bikeinn.com/bike/contine...mm/137172134/p
https://www.bikeinn.com/bike/bike-pa...1)+asc&start=0
https://www.jensonusa.com/Serfas-Road-Presta-Valve-Tube