Ferrari might have made the decision to spend their way to success (their statement does not explicitly state that they are going to spend big). They have a great team, but at present they cannot "break" RBR. They need to spend big money, to "break" RBR, so this might be the plan.
Next year should be very interesting, IF Ferrari have decided to remove budgetary constraints.
Ferrari does not have the money to compete with Red Bull in a spending war.