They have a choice.  It's extremely unlikely that any time in the last 2 years there has ever been a point where there was not a single valid and non-spam transaction waiting for confirmation even at the exact time a block was solved.

EVERY chinese pool currently is making the choice that is bad for bitcoin.  The excuse is that internet connectivity in China to the outside world is shit.  The workaround is to not rely on their full bitcoin node to see the newest block on the network, and instead use active listening connections to other sources to see a new block header (not the whole block).  If they see a new block header, they'll immediately push out new work using that as the previous block, without doing any validation (because their node hasn't seen the full block yet).  The only way to do this is by making a block without any transactions because you don't know what was actually confirmed in the previous block.

Even after it was clearly shown this is a bad idea (see the soft fork earlier this year the chinese pools caused), they have stated they have no intention of stopping this activity.  So now the rest of the network has to live with pools that don't do their fucking jobs, causing longer transaction confirmation times, because miners are too stupid to stop mining on pools that are actively hurting the network.