I doubt you are saving the fuel pump by putting another filter inline. The way the thing works (to my understanding, never had one apart) coupled with the size of the fuel lines, indicates to me that small amounts of junk passing through it won't hurt anything, definitely not plug it up.
The stock pumps last 100K miles plus without any additional filter stuff, I doubt you can ask for more from a part like that.
Probably could have done a better job with the carb filter, but you have to agree that making something the way GM did, which allows idiots to keep driving even if they never change the filter, is fairly ingenious. Besides, it prevents further fittings in the fuel system, which is definitely an advantage.