Back in the good old days, rice was harvested by hand (and sickle), straw was a very useful by-product. The process as you see are many stages. But once sicled and carted to a more convient area, latter stage work can be done (off the fields; near home; less travelling). One transport trip collect both rice and straw. And that was good (because transport was costly). 

Today, on broad-acre rice growing, machine harvesters pick the rice husks first, then a (tractor-attachment) slashers, sweepers and balers follow. Sometimes, they also set fire to the stumps before tilling the land (again with tractor-attachment tillers).  And this is used to be good (because fuel has been cheap).

New thinking is looking at one single harvest for both rice and straw again. Using some straw as fuel to power rice exracting and milling processes (to reduce fuel cost). Human is very energy-efficient much much better than machines (if human woukd only use energy to do good ;-)