Apparently, Rob Manfred is having trouble with this, so let's figure it out for him
Paying people for the work they do is apparently a controversial issue in the baseball world, with hundreds of former minor leaguers having to file a class action lawsuit because they get paid less than federal minimum wage. Baseball has responded by saying they can't do that and they don't want to do that and can lawmakers please write bills saying they won't have to do that. Fangraphs had a good write-up on some comments commissioner Rob Manfred and MLBPA president Tony Clark recently made about the issue, with Manfred's money quote being this:
When you’re eating in a clubhouse with a spread that the employer provides, is that working time, or is that your lunch break?