That's bs I do state inspections in mass and nh is way more strict I see shops In nh that pull wheels and check brakes along with a few other things that are not needed
In mass we do check altered vehicle height and tint but it is at the shops dicrection to pass or fail, we check obd2 on models 99 and newer and only safety on 98 and older. We check to make sure every light on the vehicle both factory and aftermarket work. Check for wipers washers horn ebrake, front end tire tread gas cap, rot, rear view mirror, altered exhaust, seat belts etc etc
So having brakes is not important for safety? There are some things in NH that are absurd - like how the state tried taking my license for having tinted windows on my car. Most places will pass you if it's not a rot box, have good brakes, tight front end, pass emissions (96+), all lights work and you have decent tires. You also probably won't be bothered once getting it inspected, unless something is obviously wrong.
Altered exhaust? In NH the only exhaust law "on the books" is that you must have a catalytic converter if your vehicle came with one, and must have a baffled muffler. Aside from that it can be as loud as you want by state law - although you'll need to be careful since many towns/cities have their own noise ordinances that you can get citations for breaking. And as you said, it's at the shop's discretion on if they want to put THEIR inspection sticker on a loud vehicle.
I also heard MA has some crazy formula where you input the wheelbase, track width, tire size, some other stuff, divide by a constant number, and that gives you the number of inches you're allowed to lift it - or something along those lines.