Simply put, they can command it. US GDP per capita is ~1/3 higher than in Germany, as is the median income. It's why companies like Softlayer or Rackspace, with relatively high prices, built such substantial businesses in the dedicated space years ago: US businesses could afford it.

The underlying cost structure is also more challenging in the US for most dedicated hosts. Building a data center in the US, as with most infrastructure, costs more than it does in Germany.

When you account for the higher cost of infrastructure and the higher productivity (economic output), a $80 Hetzner server becomes a $120 or $140 server in the US.

It's the same reason housing in Australia is so expensive (their incomes have skyrocketed over the last 15 years), or why the cost of living is so high in Switzerland (very high incomes). If you cut US GDP per capita from ~$57k-$60k down to $28,000 (just as an example) - dedicated hosts in the US would not be able to command the same high prices, the market would not bear that.