wtf are you talking about.
What you were using is called the Fallacy of Division, where you imagine that something true of a whole is also true of any part of it. Here, that anything dense must be composed of things which are themselves dense (and you mistake density to mean they would contain more mass than they normally would rather than having the same mass but occupying less space, too), rather than a great density of things which are not themselves dense. In the example of bricks in a field, you change from having only a handful distributed around an entire field, to a compact sphere with none of the spaces between; the resulting sphere is denser, but simple measurement will tell you the bricks themselves have not changed aside from getting closer to each other than they were.
This, on a much, much greater scale, is what is happening in a neutron star; the
atoms in it are compacted to the point there's virtually no space between nuclei rather than the atoms being mostly empty space as they normally are. This correspondingly hugely increases the density, but it doesn't mean the subatomic particles that form the nucleus have themselves got heavier; there are just many, many more of them in a given space than in normal matter. Even if they
have got denser, this will mean the protons have become
smaller than they normally would be, not that they somehow weigh more than they normally would.
This is what I meant with the example of the mountain; imagining a proton from a neutron star must be incredibly heavy because a neutron star is dense is like imagining a tiny pebble from a mountain must be incredibly heavy because the mountain is heavy. It's the same fallacy.
To give an easier example of why density doesn't make a given object heavier, when you crush a car you turn it into a small cube. That cube weighs as much as the original car. If you then stack them together you can fit multiple car-masses into the space occupied by an uncrushed car, but none of those cubes would weigh more than the cars they were originally; they're just smaller, which allows you to put more of them in a given space.