Originally Posted by Camaro 69

Pick one:
1) The stock in tank fuel pump may have died, and the owner didn't want to mess with replacing the original and just installed the external pump because it was easier. Leaving the stock inoperable pump still connected can cause a restriction and make the external pump work harder, shortening it's life.
2) The previous owner purposely installed the external pump to do away with the in tank pump, whatever his reasoning was.

All fuel injected cars since the 1980's have had in-tank fuel pumps. It won't cause the tank to blow up, even in a crash.
Also, does your fuel system still have an operating return line? A return gives relief to the pump motor by returning unmetered fuel to the tank (to form a loop), instead of having the fuel get stonewalled at the end of the line. Generally, a pump without a return in the line will work harder, run hotter, and live a shorter life.