Most borrowers have some financial cushion so the impact won't be immediate; spending an extra $380 is manageable at first. But it's safe to say there are some who will find themselves in budgetary difficulties a year or two down the road.
These loans can be of value for people who want to save or invest the money they would have paid in principal, ... Unfortunately, the way the product has been pitched, borrowers have been encouraged to stretch their budget to buy more house.
Expanding your menu (as a lender) to include as many loan choices means you get a better opportunity to scour borrowers out of niche markets.
If you pay points up front, it's harder to get your money back. When rates are high, borrowers have to pay points to trim rates any way they can, but with rates so low there is really no need to pay those points.