Answer:
The practice of dowry is common in Terai, and people from this region freely welcome dowry as a right to groom's side. My hometown is Saptari, which is epicenter of Terai region. Living in this place is pretty much advantageous, but it has some problems too. Though dowry is mainly practiced in Terai, it is spreading other parts of country too, which is bad.
Dowry system is not as severe as it was before, but it is very common and demanding at the same time in Terai. Now you can see almost every people who married recently has motorbike given by bridal side. Few years ago cycle was in Trend, which I know of. In many places of Terai marriages don't get fixed because of dowry, which you can see now a days too. I have seen many examples of this trend, of course, in my family too.
The dowry tradition was/is strong in the Terai districts bordering India, and there's a sporadic incidents of bride killing/burning/beating/acid attack over dowry disputes. More often, husband or in-laws seeking additional dowry physically abused wives or forced them to leave.
Dowry is known as 'dahej' in our places ('daijo' in Nepali) is one of the social dangerous evil of our country. Because of dowry system parents started dreading the birth daughters in the family, which is very sad. In some parts of WORLD, disputes related to dowry sometimes reault in acts of violence against women, including killing & acid attacks, which is very worse too.
The custom of dowry is most common in Terai because people living in this place strongly practice patrilineal, and expect women to reside with husband's family (which is common in whole Nepal). Also, in Nepal weddings are usually seen as a chance for ostentation & display of wealth, which most family actually don't even have.