The Grammy-winning artist held a surprise album signing Thursday at the business. His new album "Damn" was released on Friday.
Fans said they hoped to take photos with Lamar and that he was one of the greatest rappers out there today. One fan said he was hoping to show Lamar one of his own rap songs.
In an exclusive interview with Eyewitness News, Lamar said he was glad to show love to his hometown.
"It's only right for me to show face and come back homegrown, where I'm from," he said.
He said he hopes that his success story inspires other young people.
"It's inspiring, period," Lamar said. "If I see my favorite artist or someone that I admire, it would give me so much motivation being a 9-year-old or 10-year-old or 20-year-old kid. I just know what type of fire it would put inside their heart, to continue doing whatever they're doing. Whether it's furthering their education or playing sports."
Compton Mayor Aja Brown went to the event to personally thank Lamar, who she said has done a lot for the community where he was born and raised.
"He's very, very impactful in the way that he wants to help grow his community and to really be present. He's not a fly-by-night and he loves his community. He definitely puts his money where his mouth is and most importantly, he brings his time and his presence," she said.
One fan said Lamar's music and lyrics have helped her through tough times in her life.
"He's impacted a lot of people who live in this area who've been through hard times and stuff," she said.
Early estimates indicate Lamar's album may sell 560,000 units within a week of its debut.