Why did they all change names???

[Chester Melin]

My ancesters name was Anders Abrahamsson His sons were Abraham Melin My Great grandfather and 3 others who's surnames were Palm, Bergstrom, Lofgren (all musicians). Is there a reason they all had different names and wouldn't swedish naming conventions made them all Anderssons?
 
Could they have been ashamed of the name or is there some other naming rule I'm not aware of?
Thanks

[Anders Andersson]

A lot of people adopted new surnames during the 1800's. There may be several reasons for this, but I guess one reason was increased migration and urbanisation. Back in the old village, it was convenient to refer to people by their family connections (Abraham, son of Anders), but when the sons moved to another parish (perhaps to the town to find work), their patronymics were meaningless to their new neighbours and coworkers. Adopting a new surname provided some distinctiveness compared to being one of several Anderssons in a crowded neighbourhood.
 
My own grandfather and great grandfather were both born in the same parish in rural Sweden, something I believe contributed to our family retaining the patronymic for an inherited surname.

[Elisabeth Thorsell]

Chester, you can read more about Swedish names here