The rates listed for the $A are off-shore rates, and do not reflect the reality of living and changing money in Thailand. I am however surprised that there is such a difference as I would have expected a greater correlation.
For interest the $A hit a high of 0.882 against the $US about 2 weeks ago and is currently 0.787, down about 11% which suggests that the on-shore rate for the $US v baht has shown a slight appreciation.
Make no mistake about it, for any Aussie currently converting to baht......they're getting 10% less than they would have early last week, unless they were ill informed enough to convert overseas in which case they would be even worse off.