I think that it's not legally fraud (in the US) because an important component of fraud is that the lie is used to steal something of value from the victims. Advertising a job that doesn't exist doesn't do this unless you're charging an application fee or using the data collected from applicants for a purpose other than what was represented.
The practice is lying, though, and I'll join in the chorus of voices saying that it's terrible behavior.
False advertising is considered a type of fraud because you used false facts to extract, or try to extract, value from someone. If there was no job open, you just cost someone paper, ink, transportation, and time. It's a stetch, but in my book it fits.
The practice is lying, though, and I'll join in the chorus of voices saying that it's terrible behavior.