(Cover) - EN Showbiz - Zac Efron thrilled staff at a San Diego hotel over the weekend by leaving them a 40% tip.

The kind-hearted Hollywood heartthrob was partying with a group of friends at the Float Bar at the Hard Rock Hotel on Friday night. Zac was determined to ensure his pals had a great time and was so impressed with the bar service, he left double the expected tip. The group splashed out over $700 on alcohol including premium vodka and tequila worth $350 a bottle and cans of Red Bull energy drink, meaning the gratuity should have been $140. However, Zac decided the staff had been so efficient he handed out an extra $150 when he left.

"Sources at the hotel say Efron covered the $140 service charge on his bill... then dropped an additional $150 just for the hell of it. Grand total - $1,093.50," reports TMZ.

Zac and his friends were keen to keep a low-profile at the nightspot and were spotted laughing and joking as they partied together. (C) Cover Media