They store your passport info, entry data (point of entry, entry date etc), fingerprints and picture plus possibly some additional data that immigration official enter the system. "Losing" the passport wont help.
Thai embassy in Helsinki, Finland just released the requirements and application procedure for STV. I haven't seen a list for approved low risk countries yet, but Finland citizens can now apply for STV.
2. Passengers arriving from China (People's Rep.), Hong Kong (SAR China), Iran, Italy, Korea (Rep.) or Macao (SAR China) must have a medical insurance with coverage of 100,000 USD.