system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are airplane tickets are so expensive in America compared to Europe?
gpt
America is a large country, so flights may be longer distances, on average. In addition, Europe has a very competitive train industry, meaning that the airlines have to compete with it. America's trains are much more limited and expensive, so they aren't much of a competitor to airline travel.