Its not that sonar 'cant' do the same thing but rather an issue of workflow and ease of use. Sure Sonar can create Markers and Tempo change but the reason so many of use programs like Vegas for this is 'ease of use'.
Why is an La2a so popular?? sounds great, powerful and easy to use. To be able to trim and move the Video clip to match would just be basic edit functions as many other audio apps have had for a while.