An awkward silence filled the room. Robinson let it sink in, then turned away, sighed a loud sigh and said - cheerfully, mind you - "Oh great, I've got a neo-Nazi in the first row."
The crowd laughed. The show went on.
Although that sort of thing occurs less often now than it did when Robinson started out six years ago, it still happens. Usually, the comic says, these jokers are actually trying to be friendly.
"One guy came up to me after a show at the Comedy Factory Outlet, and he's, like, joking with me, and then he says, 'I'll tell you one thing. I don't like my blacks unless I own 'em. Yeah, I love my niggers when I own 'em.'
"Just like that. He's laughing like this is funny and I'm supposed to yuk it up with him. If that's the case, I might as well say, 'Yes, sir' and shuffle my feet a little bit and do a little minstrel show for him."
Being a black comic working mostly white rooms, Robinson, 27, has learned to get his message across with humor. Right off the bat, he attacks people's prejudices.
"I've had a rough year," Robinson told the Mount Laurel gathering at the opening of his set. "This whole year has been rough. Ever had one of those years where nothing goes right? At the beginning of the year, my car was stolen. The thing that hurt me the most, I knew who took it. Those damned Jewish kids."
The room chortles.
"They're probably somewhere in Cherry Hill joy-riding right now."
Shrieks of laughter.
"I try to get a little information across," explained Robinson, sitting in his living room in a Yeadon apartment complex the other morning. "I want to let folks know that everybody's the same. We all have our fears, our insecurities or whatever, but we're all the same. I bleed just like any other man.
"The only difference is a little shade," he said, pinching his skin.
In his routines, Robinson tries not to get preachy. He leaves that for the younger of his two brothers, Daryl, a pastor at the Philadelphia Revival Temple. "There's some irony for you. I get on stage and make people laugh, he gets on stage and makes people - well, he makes them weep."
In his act, Robinson tells another story - based on experience, as much of his work is - about playing one of the Atlantic City casinos.
"I played the Trump Plaza about a year ago," he told the crowd, waving his arms, walking around. "It was great. They gave me the complete star treatment. They sent the limousine to my house to pick me up. Big giant limousine to pick me up! I had a giant suite at the Trump Plaza. The thing that really brought tears to my eyes, though, I have to admit, the day of the show they sent security guards to my room to escort me to the show. Escort me to my show! The only problem with that: People were walkin' up to the security guards saying, 'You got the bastard! What'd he do? I knew he was going to cause trouble.'
"Little old ladies walking behind me throwing nickels at my back yelling 'Get the hell out of here!' "
Says Robinson, who has been a full-time comic since 1987: "I try to let people know that if you can accept me on stage as an entertainer, then you can accept me as a man. . . . I don't like to get too militant or whatever. When I first started out, I came on stage with my hat, my designer Cazal glasses, and I'm on stage and I was like real, real angry. But I've changed a lot, and for the better. I've come more to know myself through being on stage. It's almost been like therapy."
Comedy, the art of self-revelation?
"Yes," he affirmed. "If I wasn't in comedy I'd probably be ignorant about a lot of things. Comedy opened up my mind."
Robinson's comedy career started in January 1984. It was a Thursday, and he was taking the Route 42 bus to the Factory Outlet's open-mike night.
"I didn't have anything written down," he remembered, "because I never really write anything down. I shoot from the head. But I was on this bus, and I was writing jokes in my head and thinking: 'That sounds good, yeah.' But when I went on stage, everything disappeared. I had to just wing it."
Robinson went over pretty well that night.
"I thought I was hittin' on something. 'All right, this is easy!' "
The next night, Robinson tried the open-mike at the Comedy Works.
"I bombed like anything," he recalls. "And the following week, back at the Factory Outlet, I bombed. It was like, 'Oh, maybe I should just go back to school, give this thing up.' But it's worked out. Lots of good things have happened."
Those good things include Comedy Express, a company of 12 to 15 black comics founded by Robinson and including Nick Reed, Ralph Harris and Rocky Wilson. The troupe tours campuses and concert halls, playing mostly to black audiences. Schlitz Malt Liquor has sponsored one such tour, and the Prism cable network gave the group its own special.
Robinson's brand of real-life humor has also been seen on the Black Entertainment Television cable net. In October, Robinson is scheduled to do It's Showtime at the Apollo, the syndicated series that originates from the legendary Harlem theater.
"Coming from the neighborhood I'm from, I've been lucky," said the comic. ''I'm getting noticed, and it's not like, Keith Robinson, caught doin' something illegal."
Robinson's childhood was a rough one. His father died when he was 10. The family had a lot of addresses: 32d and Dickinson, housing-project apartments, a ramshackle farmhouse in Maryland.
Where he grew up, said Robinson, "everything around you leads to trouble unless you lead yourself away from it. It's easy to be led into different things, but I chose to do something positive for myself. Work my way up to the top."
He's still working at it, making jokes as he makes his way.