We know Kanye West spared no expense for his wedding to Kim Kardashian. One thing he did save on was Lana Del Rey, who performed at the rehearsal dinner. Reports claimed the songstress was paid around $2.8 million for the event, and her reasoning to do it without pay might shock you. Find out below!

TMZ stopped Rey at LAX and she told a cameraman of her good deed.

"I would never let a friend pay me to sing at a wedding," she said.

Well, we can't blame her!

Kardashian is a big fan of Rey's "Young and Beautiful," which West had an orchestra play at her proposal.

She also seemed to be a hit with the guests, who were left in tears at the spectacle.

"Kim and Kanye love her and were so happy she could sing for them," a source told E! News.

"Everyone was crying! So beautiful."

"Epic night in Paris," another insider adds. "Everyone was crying because they have never experienced such a party!"

It also made good publicity for the star, whose new single "Shades of Cool" dropped this week.

Rey's new album "Ultraviolence" debuts in the UK on June 16. It was produced by The Black Keys' Dan Auerbach along with Rick Nowels, who was behind hits "Summertime Sadness" and "Young and Beautiful."

"We were only scheduled to do three days, and then she stretched it out to two weeks and we finished a whole record. She's the real deal," Auerbach praised of Rey.

"She impressed me every day," he continued. "There were moments when she was fighting me. I could sense that maybe she didn't want to have anybody think she wasn't in control because I'm sure it's really hard to be a woman in the music business. So we bumped heads a little bit, but at the end of the day we were dancing to the songs."

Are you surprised Rey performed for free at the Kimye rehearsal dinner? Let us know your thoughts in the comments section below.