In Scoot you pay for everything. Water is 4 usd. Personally i would buy a bottle from airport as well as high calorie small unsalted snacks like casius or hazelnuts. They ask with pre departure e mail from passengers not to bring food in the cabin. They may also offer you to buy one or two empty seats next to you, as well as premium upgrade. If u see a passenger using a whole row seat for himself its because he paid for it. And theres no refund policy even if they cancel the flight by their own fault.
From Athens, they are a bit relaxed, not checking baggage weight from what passengers say.