Burning the Mid night oil

What's with the attitude that the “Advertising' Industry does not have to pay time and a half nor do they honour time off if not financially remunerated.
On most contracts in this industry it states that you may be expected to put in overtime from time to time.... yet I find that this clause gets abused to the full extent.
I have also noted through the years how youngsters are taken for a ride as they are desperate to get something on there CV / Portfolio etc..