Andy,
I think the distinction b/w your two examples is that a night out with the boys is an inherently social thing, and as such, is not generally considered out of place if brought up in a social context. Now, while some may practice drinkin' and skirt-chasin' with the passion of a religion, an unsolicited invite to a religious meeting would be considered socially awkward by many, offensive by more than just some. To be fair, I think the same would apply to someone coming out and suggesting a night in the strip-club to his/her crew completely out of the blue (wow, I just equated Jesus with a lap-dancer!).
I don't know if the above guy's invite was related to work, but everyone knows the old rule-of-thumb against bringing up religion or politics in the cockpit; people get too worked up about it and the passions they stir up can interfere with one's ability to conduct operations smoothly.
Religion is a private matter. If you want to be social in a religious context, do it at church/religious-themed events, etc.
Just one guy's view, FWIW...
P.S. (and I don't me this to be taken personally): I know there are some places where religion is more tightly would up in the whole social/political scene, but you must admit that one of those places in the mountains of the western U.S. is "unique" among these 50 states.
