Chris Brown on Valet Beef: All About Principle!

Chris Brown can obviously afford $10, but he says the reason he lost it and exploded on a valet last night was because the guy tried to shake him down.

Sources close to Chris say the valet at PINZ bowling alley in Studio City, Calif., was supposed to charging $5 per car ... until he tried to charge Breezy $10.

The R&B star believes he was singled out because he's famous, and wasn't having it, growing more heated when the valet refused to back down.

Chris' camp - which tried to calm him down - said it was never about money, just the principle of the thing. Whatever it was, he was in some mood.

In the last 48 hours, Brown reportedly got into a fight with his bodyguard on board a plane in Bermuda; Big Pat had to hop his own flight back to the U.S.

After that, he feuded with the valet outside a charity event at PINZ ... then went to the Emerson Theatre in Hollywood and told the crowd "F--k Drake!"

A day in the life ...