I use dryer lint and corrugated paper-board. The dryer lint catches fire if you sneeze in its general direction and once the corrugated paper board is lit, it burns very hot because the corrugation acts as a natural chimney.
Dryer lint is likely to be plastic particles rather than natural fibers, depending on the materials you’re washing. You may not want to use it indoors or to prepare coals for cooking.
I tried drier lint. My issue was that it smelled _horrible_ as it burned. I doubt this matters very much for the food, since the starter is long gone by the time you start cooking, but I just don't want to be around it. Newspaper/brown packing paper is plenty cheap and available for me.
Along with other issues stated, I already keep my dryer lint as an emergency tinder supply for survival situations (or the occasional campfire mishap).