The one thing and probably the biggest thing about us in the northeast.....
We also have natural gas available to many of us. Most with oil that can get natural gas will go that way... honestly its a no brainer. People don't want to kick out 3-5000k for a space heater, many have believed the promises of eager pellet store stories of " yes it will heat your entire house" and "its simple to clean" and " it only needs cleaning every now and then"
Many pellet stoves were on sale after the last oil crisis as people weren't happy with their stoves due to the promises that weren't always true, or the work they didn't know they had to do.
Now us pellet guys know better, and while they aren't incredibly difficult most people say over 60 don't wanna lug bags around and lift and clean stoves,
At the price of stoves and pellets for a new burner, you are much better off and smarter to upgrade your furnace (vs oil furnace).
Another thing in the northeast- new England area many are prone to ice storms or power outages that can last days or weeks, those people tend to head towards wood stoves..
There are many pros and cons to pellet stoves. What I don't like is the swing in pellets, and maintenance/repair fees...
I clean my own stove, rather often but still have had to replace gaskets, esp sensors, comb. Motors/fan on a 2004 stove, not bad... however my furnace has never broken down and its a 2002.
For me, I would need a pellet boiler or another stove to completely heat my house, which would double my pellet purchase at least.
So, I do plan to take out my oil burner and replace with Nat gas burner at about 83-86% eff witch will run about 12-1500.
But that will be for back up to my wood stove and pellet stove
Another reason is resale , most people buying a house would rather a new furnace than old one with a stove.
If the price of pellet stoves came down there would be a lot more sales than what there is now . But right now many of the nice stoves are very close to the price of furnaces.
(this is oil vs pellets with Nat gas availability)