Some hotels have SPG Instant Awards brochures laying out in the front desk and sometimes you may find them in your room/suite as well. You can just use your Starpoints towards folio expenses and for dining, spa etc.
Here Are The SPG Instant Awards Offered By Le Meridien Jakarta:
You can use 375 Starpoints for $5 credit in your hotel folio. This values Starpoints at 1.33 cents each. This 1.33 cents per Starpoint must have been set by the SPG, as I have never seen any other value used.
These brochures usually list of number of activities and their price in Starpoints.
Redeeming your Starpoints towards these instant awards rarely, if ever, makes any sense. If you have more Starpoints that you can EVER use then using your points towards these services/activities can make sense.
Personally, I can never see myself using Starpoints in this manner, however.