I think Noodol Cafe is connected to Platinum Promotion/Passport (agency for PASSPO, palet, predia, 3min, FYT, etc) so they may have worked there before but, when I went in December it was mostly girls that hadn't debuted with a group yet.
http://noodol-cafe.com/Basically you buy a ticket for instant ramen or a soda (500 yen for someone random, 800 yen if there's someone you specifically request) and you sit and talk with them for 3 minutes until the ramen is ready. It was okay since I had no expectation going in, as in I had no idea who the girl was before I sat down, if it was someone I was a fan of, it would have been better, I think.
I saw Chu-Z announce the bar/cafe thing a few months ago but didn't go. Maybe I'll go the next time they do?
Backstage Pass has been good at times but last time it was kind of dead. That's not good for a place that charges 900 yen for beers but, then again AKB48 cafe is about the same price and there's even less interaction there.
FC events are different since the fans usually pay up front (membership fees plus the cost of the event).