Problem with the thermal label printers ala P touch for large batches of the same label is the handling of the tape. You print out a bunch of labels, then the tape curls up when you remove the backing and it is a gawd awful mess. You either fiddle with removing the backing on each individual piece. Or you deal with this curling mess... You eventually learn to cut each label partway so you can peel the backing off in one piece, ripping each label off as you go and sticking in on the edge of your bench. Then you got a big row of labels, ready. And then eventually you learn to just stop using this expensive and cumbersome device for anything so temporary/disposable.
I got addicted for awhile.... but it is just more trouble than it's worth.
Honestly, laser printer for large batches of the same label. Can't be beat for price or convenience, once you get the template setup.
Most of my labels are hand written on white paper tape, now that my P touch kick is over. It doesn't stick so good to the bag, so I cover it with packing tape. Basically, what Rick Law suggested.