Every year thousands of poor people move to Jakarta from the countryside to look for work -- only to discover that there IS none. So they invent work. Hence, the Umbrella Man.
Umbrella Men are usually just boys, really; more rarely they are girls or a grown man like this guy. They hang around popular destinations like shopping malls and offices during rainstorms, and as people approach or leave the building, the umbrella boys swoop in and majestically hold umbrellas over their heads. For this they generally get a thousand rupiah or about ten cents.
This guy was pretty dry but the boys always seem to get soaking wet, partly because they have to hold the umbrellas so high, and partly because they play in the puddles -- even kids who work are just kids, after all.