'How does not giving *points have ANY effect on the fact that the person did, in fact, stay more than 30 days?! '

Well it looks like a pretty strong disincentive to stay over 30 days if you value the Starpoints.

I believe the reasoning runs thus:

- *W want to make a profit and encourage people to occupy rooms.

- *W operate SPG to cultivate customer loyalty.

- *W do not want people to stay at a single property for over 30 days on a single stay or *W face potential legal and/or tax issues.

So:

- aware of the legal issues they state clearly in SPG T&Cs that people will not receive Starpoints for stays over 30 days in order to encourage members to check out after 30 days, stay somewhere else for a night and come back to the SPG property.

Where this falls down is that *W assume that members will read the T&Cs and act logically. In fact, as the OP and several other recent threads show, what some people do is vent against this perceived injustice. Possible motives for this include umbrage at being made to look silly or the hope that shouting loudly or long enough will bring about their preferred outcome. Some companies simply roll over at this point and cave in the name of 'good customer relations'.