For what it is worth, (and that may be nothing), I have read that oftentimes the earliest versions of Hobo stoves were made out of spike buckets. When railroads (at least the ones in the U.S.) are replacing rails or cross ties, they drop off buckets of railroad spikes every so often. These buckets are probably about three gallons, in size. Since they are made to hold very heavy spikes, they are quite heavy duty built. Oftentimes, the railroads did not bother to pick up these buckets and the right-of-way was littered with them.
They were readily available to anyone near the rail road tracks. Here in the U.S., back during the Depression, there were wooded areas near the tracks and near towns that often held dozens of hobos. Supposedly, they all went out and "bummed" (begged) whatever food they could, and then cooked a big communal stew out of whatever was brought back. Only one stove was needed. They were not small nor compact, and no one took one with him. The next hobo "jungle" down the line would already have a stove.
Small hobo stoves supposedly evolved later and were used by loners who avoided the "jungles." In point of fact, there were probably very few historians living the hobo life and it is for the most part anecdotal evidence. If someone has a different version, I would not argue the point.