Why does the seafarer choose a life at sea in spite of its hardships in "The Seafarer"?For example, like the feelings he expresses and the problems...

In the Anglo-Saxon work, "The Seafarer," the speaker
refers to himself as an exile.  He has no home but the
sea. 

First, his former world vanished.  His lord and
protector, it seems, was in the past killed or vanquished and conquered.  The speaker's
home was lost.  He mourns for the loss of his way of life:  thus the poem's status as an
elegy.  The speaker would have been a member of a community led by a lord.  But central
government did not exist in Anglo-Saxon England.  Might, indeed, made one right during
this period of history in England.  Communities came and went quickly, or came then
changed leaders and members quickly.  The losers of a battle were kicked off the
land.

Since living in exile, the speaker has,
apparently, developed a prejudicial us-them attitude toward land lovers, as we might
call them today--those who don't spend most of their lives on the sea.  Land dwellers do
not suffer like he does, according to the speaker, and thus he is bitter toward them. 
 

Since he doesn't have the home of his former years, and
since he despises those who live in the cities, he spends his time on the sea, though
suffering is often the result.

There is also a small bit of
the speaker simply being a person who wants to travel and see other people's homes and
distant lands.  As he writes, his "heart wanders away," and his "soul roams with the
sea."  This urge to wonder, however, is clouded by his loss, his suffering, and his
hatred.