"Speaking for only where I live in the US. We see the occasional "service charge" added to a bill and there is usually an explanation to it. But when we "travel" we pay attention but also treat it like we do when we dine around our area. We've been told it's a generic charge to offset raising the rates on a menu. That being said, we've also been told at restaurants that we truly trust that it goes to the whole staff. That statement doesn't track for all restaurants. As someone who grew up in the service industry I would never trust all the owners to be honest and take care of their staff. But I would like to think that maybe the bulk of them are possibly treating their staff a little better with the "service charge". And in our opinion, regardless of the "service charge", we will always tip out our service staff on top of the service charge because in most establishments they have to pay down to those who help."

Yeah, the explanation is they don't want to pay to re-print the menus so instead they add a service charge.