You can tell how tight and comfortable a group of people are with each other simply by the subject matter of the conversation. If pedestrian observations are passing as stimulating conversation then the people don't really feel comfortable with each other so it's not really you, it's them. Is it a group of friends that has a stable core? Do you all kind of know each other, but don't really know each other that well? Will they ever feel comfortable enough to engage in conversations you find stimulating? Well, who knows, somebody has to try and see what happens. Just sitting and sulking the the conversation isn't exciting enough doesn't make it more interesting it just makes you salty.
I've been in a situations myself where people are talking about how drunk they are, somebody's drinking a Guinness, somebody wants an Irish car bomb, we start talking about Ireland, then next thing we're talking about the current state of affairs in Ireland, why you don't hear much about it in the news, then from there we're talking about how to define a terrorist, terrorism, the conversation just shoots off from there.
I guess in my mind, there's always a way to take a current conversation and segue it into something at least I find interesting and it's a totally smooth transition. Those who aren't interested in the conversation will drift out and those who are interested will drift in.
If you're in a large enough group (8+), there are at least two other people guaranteed to be as bored as you are. If you look you will see the feigned half-hearted interest. Strike up a conversation with those people. If yall look like you're having a good enough time other people will join in.
I think of groups of people in chunks. It's like they zoom in and out to me. I see little dashes going from one person to another. These group activities are platforms for you to find people you're more interested in. You're there for the group inasmuch as the group gives you a bank of people you may want to get to know better.