The latency with satellite internet can never get below about 550ms or so due to not only the infrastructure, but especially the distance the signal has to travel.  It's approaching 90,000 miles or more.    

With regard to streaming, be careful, as it uses a lot of data, especially when done in HD.  When you run out of data your service will be throttled to a lower speed.  You can buy data tokens to stop the throttling, but that can get expensive after a while.  

Because HughesNet uses shared IPs, and because they change all the time, your shown location will also often change.  

They should have given you correct information about online gaming with satellite internet, especially concerning real time games. 

If it's been no more than 90 days since your sales call you can request that it be reviewed.  If it's determined that you were not given the correct information you may have some type of recourse regarding the Early Termination Fee when cancelling.  If you wish to do so, you can request that review in the "myAccount and Billing" section.