Triple Weber fuel line question

I've seen a handful of people both at the classic datsun show and elsewhere who either did not have or did not use the supplied fuel line for their triple set-up. This is the one that looks just about identical to the stock one, ie with the fuel return line.....

These people have the fuel coming from the tank to the fuel pressure regulator and then usually via stainless steel lines and AN fittings to the the carbs with no provision for a return.

Why? What does this change? nothing I am guessing.... Did they just plug up the return to the gas tank?

Am curious to hear what you all have to say...

-e