I believe this to be true. In regards to the tipping of bellboys , I have asked
some local Chinese and also recall what prompted my reply that its customary and expected to tip the bell boy.

Bell boys in general will not solicit to take your bags to your room. They may assist in taking them to the front desk but that's where their complimentary work stops. You have to request them to take bags to your room and this is a service that you must pay for. So paying them is not in fact considered a tip.

So I do consider Peter N-H correct when he says tipping is unnecessary and inappropriate in China. Tipping is probably considered stupid as this money should be used for something worthwhile like a bribe.