The most popular animal to be bought and set free is the passer montanus bird (called burung gereja/church's bird in indonesia)
why would the guy sell this birds at the 1st place anyway?? why would he go the trouble to catch them?? need time to think.......??
....insert you own personal fav thinking music here....
its simple economic's principle called supply and demand, those birds are almost of no economic value if not because of the demand from these people. stop the buying, and the catching will stop too.
YOU are the reason they end up being caged and treated badly (those seller are poor people who had trouble landing a job themself, its not exactly like they are running a bonavide pet shop, they can't really afford to keep feeding the birds and hundreds and maybe even thousand are kept inside a small cage so that it can fit behind his bike, some of the birds die inside the cage)
YOU did this to them, but yet you walk home thinking you have been a saving grace to them!!
if you really do care about the well being of these wildlife, then donate your money to one of the wild life organization fighting to help this animal, or get involve in their project. But i know for a fact that most of the people who buy those birds from temple won't be bothered, because they doesn't want to take time out of their "busy" life to actually do something meaningful, going to the temple and spend some money to buy and then release those birds take only 10min, and they can feel good about themself for days and weeks. Make me remembered an episode from the sitcom friends where Joey argure that there aren't any unselfish good deeds, all good deeds are selfish.
Somebody should really tell the temple's elders and explain it to them so they can stop their followers from continuing doing this stupid good deeds.