Used to only nobles really had surnames. When it came in vogue for commoners to have last names they tied them to a profession. Why English last names have so many Shepherds, Bakers, Millers, Smiths, etc.

Of course there is also ones tied to locations. Hill, Creek, River, Forest.

Berg = Mountain
Stein = Stone

Gold Mountain. Gold Stone.

Same reason a lot of jew(ler)s are called Silverman or Silversmith. This was a common profession for them.

This might sound like I am defending kikes and yeah, I guess I am. In the same way "they dominate the banking industry because they didn't have moral taboos on usury!" is a defense of them.