offer me any job and i will do it for bitcoin 
You can do faucets and stuff for free BTC: Automatic BTC Faucet Rotator.
Is that really a good idea? How will he ever be able to spend that dust?
Yeah, you can. It's a good idea to merge the amounts every once in a while, but most sites compile multiple payouts into one before sending it to you, so you don't get a ton of transfers.
Yep! And even if you get BTC's from other places, you just get extra with these methods, :p. It'd be different if BTC's were an infinite source but since they are finite, having a bigger piece of the pie is ever more important.