Well, not neccessarily bad astronomy, but because astronomers are pretty well used to using greek letters:
If you look at the movie poster, they use the greek letter sigma Σ as an E.
Would be interesting to hear from the BA what he read when he saw the poster the first time.
"Grssk? What the hell is a Grssk wedding???"
PS: The real fun would have started if spelling the Σ correctly in a word where it is replacing an E would have turned the word into something, er, foul or vulgar...