Troll Mating
As might be expected with a race that spends much of its time digging
for metals and gems, the accumulation of wealth is a popular troll pastime --
and a large factor in troll matings. Their courtships tend to involve large
amounts of gold and jewelry, and a troll maiden who feels she's had
insufficient finery showered upon her may well cheerfully throw over a poor
suitor in favor of a richer one. This has led to the saying "a troll maiden's
love is as true as your gold."
Still, though, trolls are not entirely without affection, and a
mated pair of trolls who has been together for a suitably lengthy period of
time may well keep together for reasons beyond wealth. (Maybe. It never hurts
a troll to keep at his mining!)