Enter the oogles to dash that optimism to shreds. They have hitchhiked or train-hopped many miles to end up at your doorstep. They have a dog and a somewhat unconventional stringed instrument in tow, perhaps a ukelele or mandolin, as well as a bunch of regional zines you can't wait to photocopy and add to your library. They talk about how reading Evasion and Chuck Palahniuk's Fight Club changed their life. They seem, on the surface, like someone committed to the lifestyle -- someone you could depend on to have your back at a protest or aid in the construction of a greenhouse.
But NOPE. It's only a matter of time before they reveal themselves to be leeches, people who have assumed the trappings of a radical in order to secure free food and lodging. They attend Food Not Bombs with you and spend more time stuffing their face than helping with the cooking. They drink all of your beer and go on anti-feminist rants, offending you and your housemates. They refuse to help out with housework, straighten up their sleeping area or take responsibility for their pet. They massively outstay their welcome, taking a positive response to "Hey, can I sleep in your backyard?" as a long-term invitation. And in the end, all you are left with is a bunch of trash and mess, a scabies-infested couch, and an ardent desire to revise your home's open-door policy. Underneath all of that flash and rhetoric was just an unwillingness to assume any sort of responsibility and a single-minded pursuit of pleasure.
I should note that the utility of oogle extends beyond describing an obnoxious house guest. An oogle can just as easily be a more transient figure, someone who attends a house show only to snatch up and consume unattended drinks and mosh a hole into your wall, or who begs you for change with a wad of 20s in their pocket. However, oogle has yet to break into mainstream culture and refers to a very specific type of pretender or mooch.
This is a hard one to trace, but according to one source, it popped up in the crust punk subculture sometime during the 90s, with some crusties even reclaiming the term and referring to themselves as oogles. But why "oogle"? Speculation abounds, but I am inclined to assume that it did derive from "ogle" -- a logical etymology, given that the term refers to someone who wishes to observe and reap the superficial benefits of being associated with a particular group while avoiding any real commitment.