Hurt most by the expanded schedule will be crew members. Most drivers have access to helicopters and private jets so getting home to relax and spend time with their families for a day or two each week during the season is not a major problem for them. But those that perform the indispensable grunt work in shops and pits are generally not so lucky. Their days are longer, their modes of transportation not generally as accommodating. Race crew has become a bit of a misnomer.
Most teams have more than one crew.
The number of crew members and their functions vary from team to team. The number of crews a team has also varies. James Ince, crew chief for Johnny Benson at MBV Motorsports, has a crew system that is fairly typical. He has a shop crew and a road crew. Almost all work seven days a week.