I also have the same feeling that thin fonts look ugly on my humble LCD screen with dismal resolution and low ppi.

I was once complaining to a friend how ugly site X is and he said it looked right to him; later when I saw his machine it has a nice display that made site X look twice as better on my shitty display.

Lots of sites are designed on (and for?) high density displays and it ends up looking awful on low resolution screens like mine.