Well in many countries outside the US, Samurais didn't come with those bars or even the roll bar-just the targa bar and a 45 degree bar that bolted to the qtr panel. The original Willys jeep, which the Samurai is heavily based on, did not have a roll bar.
As far as the install of the kit, it is pretty straight forward. Every market other than the US seems to have had it stock.