OK, so you know the word "leverage", at least. Next, you may well know that the rider center of gravity is almost exactly above the front wing. Therefore, the full weight of rider (say 60 kilos) is leveraged on 20 or so cm of fuselage in front of the mast. That is quite a force (
"lever" to be precise). This full lever (=60kg*20cm) has to be supported by fuselage strength. This puts the lower limit on how strong fuselage in front of the mast must be.
Now, since the rider is balanced over the front wing, very little adjustment is needed to maintain the balance. Any significant deviation from that delicate balance point would inevitably translate into one result: you fall. Therefore, the part of fuselage that does stabilizing is under significantly lower lever, I would guess not much more than 1kg*40cm. This means much lesser strength requirement, perhaps one order of magnitude less.
If you still not convinced, remember the times when rear wing was bolted above the fuselage? This is because it exerts the force downwards, so people were thinking that mounting it above fuselage would give the needed strength to counteract this downward force. As it turned out, it didn't really matter, and the wing bolted below fuselage with just two screws is fine. Therefore, if it is OK to attach the rear wing with 2 screws, why do you doubt that attaching the fuselage in similar way is flawed?