Open invites to every event?

I'm under the illusion that I've always, more or less, been a part of the "cool" group at church. Being on staff has usually helped.

As a result, I've fairly regularly gone out to dinner/the movies/the pub after church.

But, I've been wondering about these informal events.

Should they, if a church is to be truely welcoming, be open for everyone?
Should these events, periodically, be made public?
Should they, if organised before the end of the service, be announced during church or at the conclusion?

The reason I ask is because it's within these informal gathers that cliques are born and reinforced.
It's within this "time of fellowship" that the mindset of "us" and "them" is fed.

Of course, the danger is that new people will want to be involved or, worse still, that a newbie might not like members of the congregation outside of the pews... But, surely that's the price if you're going to be truely inclusive.