Here is some info that I posted on another board a while ago. It may help to clarify this question of deportation responsibility.
In answer to a request for further clarification on a number of points raised, please find the following. Of particular interest in the following post is the fact that:
- Taiwan does have policy that requires foreign nationals have proof of onward passage to be permitted to enter Taiwan.
- Taiwan immigration may refuse entry to foreign nationals who cannot meet the requirements under this policy.
- Airline companies have their own policies in line with these government regulations in checking documentation at check in and refusing carriage of passengers that cannot meet the requirements under these policies.
- That airlines can indeed be held responsible for the costs incurred in the deportation of foreign nationals that they transport to Taiwan in the event that the carrier has not exercised due care in checking the passengers documentation.
While these policies are clearly in place and are enforced on what appears to be a random basis, it is possible that some foreign nationals do arrive in Taiwan without proof of onward passage. Considering that you could be turned away at the check in counter at your point of departure or refused entry at the point of arrival here in Taiwan, it would seem very unwise to travel without this documentation.