Excessive "early termination fees"

I was told it would cost $800 to terminate my internet service. I am closing my business and should be allowed to terminate the contract "with cause" per Comcast Business's BUSINESS SERVICES CUSTOMER TERMS AND CONDITIONS Furthermore, it was not explained to me that the contract was for three years when I signed up for service, which is the only way I can get internet at the location of my business. I was also told by Glen, the customer service representative, that there was no way for me to speak to a manager or supervisor as I was "on an escalated line" already. However, I did not remit in my request to speak to a supervisor and I was eventually offered a "supervisor call back" after I asked Glen if he owned Comcast Business and that is the reason he doesn't have a supervisor or manager I can speak with (clearly not Glen's fault as he is likely just operating per his training to restrict access to someone who has the authority to resolve this issue further). 

These business practices seem deliberately deceptive and predatory. I am awaiting my supervisor call back and will be requesting a transcript of my initial conversation with the customer service representative who signed me up for the service 11 months ago.