Which can easily run into thousands of dollars for a weekend, so if an event wants to do, say, live streaming, they do their best to make it impossible for the event to bring its own hotspot and connection.
"Marriott employees had used containment features of a Wi-Fi monitoring system at the Gaylord Opryland to prevent individuals from connecting to the Internet via their own personal Wi-Fi networks, while at the same time charging consumers, small businesses and exhibitors as much as $1,000 per device to access Marriott's Wi-Fi network."
In your room or in the conference center you should be able to use your own Wi-Fi without interference.
Source: http://www.fcc.gov/document/marriott-pay-600k-resolve-wifi-b...