Walmart
Walmart
[Caption above the panel:] When a network tries to become everyone's one-stop hub, the Walmart of social interaction... [Cueball and Hairy standing in a supermarket, Cueball holding groceries under his arm, Hairy with a cart.] Cueball: Oh, uh, hi! Funny running into you here. Hairy: Oh, hey! Yeah! How've you been? [Caption below the panel:] ...it inevitably becomes the Walmart of social interaction.

This comic satirizes the way in which large social networks, such as Facebook (and at the time of this comics posting Google+ ), attempt to aggregate all aspects of the user's online social presence. Earlier social networks had more granular focuses; e.g. MySpace originated with a music focus, and even earlier various bulletin board systems were centered around specific topics. By contrast, many social media companies attempt to encapsulate the variety of aspects of their users' online lives, thereby aggregating their personal, professional, and private lives in a way that was previously unlikely to occur.
The first comparison to Walmart , a large multi-national "big box" retailer that sells everything from gardening supplies to televisions to groceries, is apt because Walmart, too, is attempting to aggregate various aspects of your life into a single location - but rather than aggregating your social media presence, it's attempting to aggregate your shopping habits.
The punch line of the joke is that social interactions at Walmart are awkward, contrived, and frequently undesired — just as they can grow to become in a social network that is insufficiently focused or too bloated. People communicate differently with different groups of people, and if they are attempting to connect with friends, they are unlikely to want their grandparents present. Similarly, if a person is attempting to buy groceries, they may not be interested in extended small talk with acquaintances with whom they may not share much in common (perhaps the fact that they both shop at Walmart is the biggest similarity they share).
The title text elaborates on this idea by sarcastically implying that he wants all his older relatives to hang out where he hung out in college, likely causing extreme awkwardness.
[Caption above the panel:] When a network tries to become everyone's one-stop hub, the Walmart of social interaction... [Cueball and Hairy standing in a supermarket, Cueball holding groceries under his arm, Hairy with a cart.] Cueball: Oh, uh, hi! Funny running into you here. Hairy: Oh, hey! Yeah! How've you been? [Caption below the panel:] ...it inevitably becomes the Walmart of social interaction.
