Why is sudo running so many times?
The easiest way to determine what's going on here is to open a terminal and run

ps aux | grep sudo


On my machine there are many lines, all that include:

/usr/libexec/StartupItemContext /usr/bin/open -a /Library/Application Support/iStat Server/DiskTool.app


So, we know that it's from a start up item, specficially iStat Server. 

As I don't use that app anymore, I'll uninstall it.