It depends on the nature of the job and the competition by candidates to get the placement. If there are not a lot of candidates, then you might expect the company to pony up for someone they really want. But if there are lots of positions and lots of candidates, it is unrealistic to expect them to fund an interview. Just because they contacted a candidate about an opportunity doesn't mean that they will spare no expense to get them.

Fuskie
Who has heard that some companies will send out an interviewer to various campuses as a cost effective method of attracting top talent, kind of how the kids were recruited into college in the first place...