The problem is, you're often required to provide some form of records or references proving your previous employment. If it was otherwise, everyone could make up whatever "employment history" they feel is most appropriate for the job. Employers often do some form of vetting on their candidates without telling them - and, if it turns out that you've been grossly dishonest in the application form, this can bite your lower back a lot worse than the fact that you have spent X years flying for an airline.