opinions please: taboo/selfish to interview with a firm twice?

[eza909]

Situation:
Simultaneously bid on a firm twice, for two different interviewing programs: Job Fair, and OCI.

Had interview at job fair (~1 month ago) as a prescreened, last minute alternate and got a ding letter a couple weeks later.

Now I have been prescreened for another interview with the same firm at OCI.

My thoughts:
During the first fair, it was my first interview of the season, and the whole thing was stuttered and awkward because neither of us (myself/interviewer) were expecting the interview (it was a last minute no-show).

Anyway, I know I am qualified as I've been prescreened twice for a small # of spots, and this interview will surely go better.

Can I interview at both?  Is that allowed? Looked down upon? Do I have a duty to disclose the previous interview/ding?

I'm not sure if it will be the same interviewer yet.

Any suggestions or opinions are appreciated.  Sorry for the novel.

[Dwigt]

I don't know that it's selfish, but they're going to know that they rejected you previously, so you'll probably have to knock the interview out of the park to get a callback. 

[Naked Promise]

Just go for it! What are they going to do...reject you?...