Before the retail marijuana movement, Nick Brown, owner of High Country Healing in Silverthorne, said on his busiest days anywhere between 85 and 90 people would visit his medical marijuana dispensary. Yesterday, the first day for recreational marijuana sales in Colorado, more than 500 people purchased a total of four pounds of marijuana from High Country Healing. Brian Rogers, co-owner of Breckenridge Cannabis Club, had a similar opening day, selling several pounds of marijuana to more than 1,500 customers. Day one sales of recreational marijuana exceeded medical marijuana sales for the entire month of December 2013, Rogers said. And they…