There are plenty of public places with as much people (if not more) than a typical airplane with free access without liquid/luggage/identity checks, yet they do

There are plenty of public places with as much people (if not more) than a typical airplane with free access without liquid/luggage/identity checks, yet they don't seem to be blowing up every other day. If those checks were actually deterring terrorism I'd expect those other public places with less checks but just as much potential victims be attacked instead.