On a previous visit to Singapore (Dec 2011), I had a hotel reservation and used the Airport Shuttle at the Ground Transport desk to transfer per shuttle to my hotel for only S$9.
http://www.changiairport.com/getting...irport-shuttle

This time I only have a very long transit en-route to BKK (13 Hours) and want to go into the city for the day. I want to know if it is possible to take the Airport Shuttle if I agree to be dropped off at one of the hotels to which the service runs? Or is the service subsidized by the hotels and therefore requires a hotel reservation to use it?
Comfortable and much cheaper than a taxi I hope this is a possibility?!