the reason why most were shot in the Berlin area was because that was the only place you could really cross. If you lived in any other city you could not go anywhere close to the West German border. You needed your papers with you at all times and if you were new to an area you would get ID'd at every corner asking you what business you had there. You would be interrogated and shot in a dark room way before you got to the border area.Dude - about 3-4 million migrated from east to west (there were hundreds of thousands from other side too). How many victims in border crossing ? 327 as per BBC : https://www.bbc.com/news/world-europe-40200305 . and this includes 24 border guards themselves shot.
Most of the shootings were within berlin area- because right in the heart of east Germany was literally a nato enclave. And east germany was paranoid about migrations there - not because of economic reasons but due to military/spy etc. As part of establishment of berlin enclave it got guarantees that it will not be used as conduit for human trafficking.
If you take out the shootings in highly militarized berlin and baltic sea (where it was mines)area then total deaths are just 16.
Also it is complete fabrication that east germany did not permit people to travel. In 1987 itself 2.8 million visits were made by east germans to west germans and majority came back home.
People that got visas to visit West Germany were closely vetted and usually powerful people in the communist apparatus or old grandmas who would return knowing they had family and grandkids in the East.