The Empire State Building has been struck many times, too.

And then there's Roy Sullivan, struck 7 times by lightning.

And NOAA has some stats by year. http://www.nws.noaa.gov/om/hazstats.shtml

They do split out into categories like camping, ball fields, etc. But "outside/open areas" is a pretty unhelpful one.

NOAA's 71 year history is most interesting - lightning has killed more people per year in the 1940s, decreasing as the years go by. (this is of course a US specific chart)