To me, paying towards the interview per se is sickening (Ryanair).
Paying for accomodation, transportation, restaurant and so on is absolutely standard. Interviews for Air France take 2 days. We all paid for hotac, train/airplane, etc...which I find is normal and fair. That is also the case in any industry when you're trying to knock down a deal on a job somewhere else. As someone mentionned earlier, it is not their fault if you live elsewhere.