Why are there no off road trailer companies on or around the east coast? What makes this area less attractive than the western States for this type of company?

I can tell you from experience running two companies.... East coast makes up less than 18% of our total sales. With Pathfinder Outdoors (my tiny company) out of the last 30 orders, 2 (two) have shipped east (of Ohio)

East coast has some great wheeling areas but I feel there are a few factors why it's not as prevalent on the east coast.
1- many states In the east use salt and people don't dump as much money into their cars.
2- The western half of the US has Moab, Ouray, Katempsy, Rubicon and LasCrusis. All Meccas of off road....eastern half has some awesome parks, but not hundreds of miles of trails.
3- when we moved to Ohio 3 years ago, our local business dropped to zero. We went from 2-4 installs a week to one a 2 a month max...
4- manufactures in the east have to deal with union labor rates to be competitive and keep employees. We pay forklift drivers $14+ and hour in Ohio just to keep someone around longer than 2 months.

Just my thoughts, I have put some thought into this because of what I do for a living, and this is the best I could come up with.

These are all valid points. Thank you.

Edit - I read the OP's question to be relating to off road campers, so the answer below is addressing that. I guess the points are still valid even considering he asked about 'trailers' not campers....

My insight into it is that the east coast, even the midwest to an extent, is too crowded to really "get out and use" something like an off road trailer. Additionally, there aren't really "trails" suitable for multi-day use.

When I lived in Ohio, a "wheeling" trip consisted of taking a day and banging around dirt roads and abandoned roads in some of the more rural counties, maybe a 'pay to ride' off road park like Haspin Acres or Southington.

Now that I have taken the effort to actually explore this country, and moved to the west coast because of it, I can see that the huge open spaces and massive tracts of BLM land in the west offer multi-day, truly remote adventure that necessitates some manner of sturdy camping accommodations.

Me, personally, I sleep in the back of the 4R; but some guys use roof top tents, and I've seen a few off road travel trailers out here. It's normal to see built rigs and guys who clearly wheel them long distances here. Back home you'd see the occasional built rig, but you knew it didn't truly see use. A guy back east might slap a roof top tent on for the poseur aspect - but you knew he didn't actually need it because 10 miles from wherever he was going to be camping, there was a Motel 6. Out here, there's places where there's no gas for 200 miles, let alone food, lodging, etc; which makes having a self contained unit like an off road camper a pretty cool - and truly usable - idea.

So to answer your question, I guess you put the business where it will be the most profitable. Sales and installation at the point of use as opposed to a continent away. I don't know what it costs to ship a camper, but I'm sure it's fairly pricey.

I recently met this guy and scoped out his work (Oregon, though):

TrailAgain

Navigate to his trailers page...

Have you seen these?
Inka Outdoor ? Custom Teardrop Campers » Venture OHV? Off-Road

I don't have any direct experience but believe they are from North Carolina.

^^^--- this. East of the MS River, roads are either fully developed or non-existent. "Wheeling" generally means driving to a place, riding around a while, then driving back home or back to a camp site. There are a few long-distance trails (Trans-America, etc.), but even with those you will always be within a relatively short end-of-day-drive of a hotel or full-service campsite. And most long-distance trails won't need a full-on off-road camping trailer anyway. The eastern half of the Trans-Am trail is specifically laid out for dual-sport motorcycles with a hotel and gas station at the end of each day's run.

Appalachian Toyota Roundup was held recently at one of the largest off-road parks on the east coast, but people parked their campers and rode around with out them. Dixie Run is coming up and will be the same thing.