Aser,
Your question is a good one. The need for boost pumps is a sign of an old technology engine pump, and a less safe design.
Sikorsky hasn't built a helicopter with a pressurized fuel system since the last 61 went down the line.
It will take a generation of people who have not been trained on 40 year old designs before the concept sinks in, however! I would guess you flew a jet ranger and a Huey, both of which have flight manual limitations against flight above about 5,000 feet if the fuel boost pump is not working.
The S-92, like the S-76 and the Hawk family has a "suction fuel" system. Basically, the engine fuel pump is strong enough to pull the fuel up at any altitude, and with any approved fuel. This means that the normal mode for flight leaves all fuel lines with negative pressure, and virtually no ability to leak or spray fuel if they fail, or are punctured, or if a crash separates the lines.
I can't tell you how bad it is to discover a leaking fuel line when your eyes sting from the fuel fumes, and you see fuel mist in the cabin. The aircraft is sudenly in grave danger of an inflight fire, and all you can do is fly to a safe landing, and not flip any switches in the process (to avoid a spark!) Most older fuel systems have from 25 to 40 psi in the fuel lines which run from the fuel tanks to the engine, usually wrapping around the cabin. That is about the same pressure as a household water system, so you can envision the leak from a pin-hole or crack.
The suction fuel needs a special engine pump, a design that Sikorsky championed about 30 years ago. The pump keeps itself wet enough, even when pumping foamy fuel (we call it the vapor to liquid ratio) so that there is no altitude restriction al all. The other, older designs could swap over, but the tests are expensive, and the fuel system might have to be redesigned. Falls under the question I posted earlier, "When is it time to just start a new design?"
Under FAA/JAA scrutiny, the S-92 was taken to its max altitude with fuel that had been heated up to about 140 degrees F (talk about a test pilot earning his pay!) and maneuvered, started and shown to be entirely accepting of the no-boost pump design.
Like that photo of the fuzzy dice, boost pumps are way past their prime! The probability of a fuel fire, in flight or post-crash, is very significantly lower when the fuel cannot spray out.