Every time you change the scene, then the first time you mention the characters you must do so individually and IN CAPS. In the example you gave, these are obviously two different scenes, so in the first you'd have:
INT. RESTAURANT - DAY
DAVE, JOHN, MICHAEL and BEN are sat at a table in the restaurant.
EXT. STREET - DAY
DAVE, JOHN, MICHAEL and BEN exit their car.
Subsequent mentions in each scene you might get away with 'four friends' if the four are together for the whole scene and there are no other characters.
As Scripts & Scribes said, the screenplay needs to make it obvious to everyone - not just who is in which scene, but where in the scene. If there is any possibility of ambiguity, then be specific who you're describing.
BTW, the thing with using caps for the first mention in each scene is an old convention, but more important than ever in these days of software. Some scripts reporting tools will use this to recognise when someone appears in the scene, even if they have no dialogue.