Roofing up in the northern part of the United States is much different. Roofing up north requires special procedures because of all of the Ice and snow in the winters. Before any shingles are installed on a steep sloped roof many homes in the north are wrapped in dripedge and Ice and Water Shield membrane underlayment. Ice and Water Shield membrane underlayment is applied on all edges and sometimes 2-3 rows of Ice and Water Shield will be rolled out and stuck on all bottom eaves to protect against Ice moisture back up. There are many places in the south were no dripedge is even required or installed. The same goes for Ice and Water Shield, it is not code in many southern areas and is only used mostly for valleys and questionable low sloped areas.
In many areas in the north they will build scaffolding around steep roofing for safety reasons. They get more money for roofs in these areas to cover the cost of the scaffolding. Roofers in the southern parts use only roof jacks, tow boards and some roofers will just nail 2x4s right through the singles.
Also when ridgevent is installed up north it should have a bead of caulk on both sides before nailing it down. The main reason is because when the heat dissipates it can melt ice and cause moisture to back up and travel inside the home.