TI, What you say may, or may not be accurate. It doesn't matter because it is not relevant to expats or their contracts.
The point that has been well made on this and many other threads is that Housing Allowance used to be sufficient to rent accommodation. Now it is not. Some people have tried to muddy the waters by bringing in arguments which may be true statements of fact but which are also totally irrelevant to the topic under discussion.
I do understand that Housing Allowance can be an emotive topic - especially if you are not receiving it, but the bottom line is that an expat anywhere in the world should not have to contribute anything from salary to rent accommodation. May I suggest you do some research on what expat middle managers in the Finance and IT sector etc are being paid in Housing Allowance in Singapore. It starts at $5k pcm and some get paid significantly more. We wont even mention annual holiday entitlement, guaranteed airline tickets etc.
Please try not to look on this from an isolated Singapore point of view - it's a global practice in a global market place and it's here to stay.