Mike,
Its a stange world! I really do think it is possible that there really were no positions available. My experiance of non-aviation organsiations is that they sometimes place ads for non existant jobs to survey the employment market and see what/who is out there ready and willing, maybe as a precursor to an possible bid or proposal. Agencies do it to get a filing cabinet full of with CVs to make it easier to quickly hoover up candidates for future real opportunities. This can be seen as a little shadey, but otherwise is sound planning.
Believe it or not, some organisations also do it to make it look like they are ramping up, create a false impression...taunt the opposition.