Here’s some more information.
http://rt.com/usa/news/ron-paul-rnc-convention-955/
http://www.csmonitor.com/USA/Elections/2012/0830/Is-GOP-convention-confiscating-Ron-Paul-signs
http://www.huffingtonpost.com/2012/08/29/ron-paul-convention-delegates_n_1841741.html
Apparently, the convention security technically banned “outside signs”, but only enforced that rule against Ron Paul supporters. Romney supporters got in scot free, and heckled Paul supporters during the events themselves, trying to block their signs, as seen in the video I linked to in the OP.
Why are you citing something from Russia Today?
Getting a little homesick, Komrade?