If you say that businesses are being hammered, you mean that they are being unfairly harmed, for example by a change in taxes or bad economic conditions.
To sack [British English informal] means to dismiss someone from their job [= fire]
• Hundreds of workers are to be sacked at the factory.
• They couldn't sack me - I'd done nothing wrong.
• He was sacked from every job he had.
• He was sacked for being drunk.