I think Lost had the key word here which is "new".
A "new" couple might have problems keeping their hands off each other so... not very fun to hang out with.
After a while though, the couple takes enough maturity to notice a third person.
It is also a matter of age I think. When you are a teenager and in a couple, it's basically the only important event in your everyday life.
Anyway, it's just my experience. I got with my boyfriend when I was still almost a teenager and I'm still with him now that I'm reaching 30. I completely noticed the difference and accepted it. Back at the beginning, I think it was completely annoying to hang out with us despite our best efforts (although it is also true that some of our friends were just uncomfortable because we were a couple eventhough we would not even look at each other).
Now, I think people are completey ok with the idea of coming over for a drink as the third person. They grew up and we also grew up as a couple. No one refused in a long time anyway... But that is also because we make excellent mojitos.
There's always the jealousy factor too you know. Mostly in my case, I think my friends are jealous that don't have girlfriends, so they don't like seeing me with mine. Yes it is stupid but that's the way people are I guess.
I just want to clarify once more, because it seems like people are getting defensive, I don't want them to change their relationship to suit me. I'm not upset about this, nor do I hope they break up. I'm just not interested in spending time with just exclusively the two of them. Also, I'm sure it has plenty to do with our ages, the length of their relationships, maturity levels, and half a dozen other things.
I think that it depends on the type of couple you are hanging out with, but I find that the couples that are not awkward to hang out with are definitely the exception... mostly it is either awkward or lame. It does usually make things better to have a couple more people around that are not in a romantic relationship with one another.
And slightly off topic but the fact that you should share all your secrets with your loved one doesn't exactly mean you should also share your friends' secrets with him too. But apparently this is not a common thought among girls.
The current duration of the relationship is a major factor in this, I think.
Like I have one friend who's girlfriend I kinda really don't like (nobody does, I doubt he even does) but I have no problem hanging out with him when shes around because they've been going out for like 8 years, so there's really no awkward coupley stuff going on.
If a couple is going out a few months or something then fuck that.
My girlfriend is friends with all my friends at this stage too, so there's no awkwardness there at all. My bestfriend, and his ex, and me and my girlfriend would chill as a four piece all the time, once they broke up, we just chill as a three piece a lot of the time and it's not awkward for anyone. It'd just be weird to be all over each other in someone elses company, I'd feel about as uncomfortable as the third wheel. I've been out at bars and whatever with just my girlfriend and bumped into friends who are considerate enough to ask like "Hey man we're not intruding are we? Do you want to be left alone?" that kind of thing. I appreciate the consideration and all, but don't be ludicrous. If we wanted to be alone we wouldn't be in a bar.
I agree, I think it really depends on the couple, and not couples in general. My boyfriend and I are super self-conscious about this and don't get all OMG MAKE OUT NOW WITNESS OUR AFFECTION...then again, we are also mad old.
Not going to lie, my fiancee and I are totally one of those couples that nobody should want to hang out with. We're not about to make out in front of people but we totally get lost in each other's nonsense quite a bit, leaving other parties confused/often annoyed. We totally accept our inability to carry on with more than one person at once though so we never get offended if people don't want to hang out with us lol