use what you can! :D i normally carry around a bag with tissue in it so i don't get that problem but it depends where you are reallyif your out at a restaurant or at work/school then theres normally...
This all depends on where you live. If you live in an apartment you will have to go in a can of some sort. If you live in a residential area you will have to dig a hole in your back yard, put a tarp...
We'd be awfully big and mighty uncomfortable if we had to carry around all the used food we ever had. The body can't convert to energy every last molecule that it consumes. Also, there is waste from...