Did Troy Bilt make that statement to you in a letter ? If so please forward it to CR so they can evaluate their recommendation of the Troy Bilt machine. If they did not put it in writing you may simply be hearing a hair-brained response from some individual who has no idea how to respond to your problem.
It is probably worth me mentioning that most snow blowers have no air filters on the carburetor intake, like every other lawn & garden machine. This is because there is virtually no dust in a snow storm, and the snow covers the ground, and the dirt, and the snow would melt on contact with an air filter heated by the engine in operation, and that would foul up the filter and it would freeze solid once the engine was shut off. IF . . . you operate the engine when there is no snow, like during the off season to move the machine, or do maintenance, a filter sould be affixed over the carburetor intake to keep out dirt and dust than can cause problems. Also keep the air intake covered when ever the snow blower is being stored to keep out insects. Spiders invade the small spaces in machines, and barbeque's when they sit unused. Spider webs attract dirt long after the spider is gone.
I wrote this after rethinking your problem. It seems unlikely a company like Troy Bilt would build machines that won't run properly on the gas sold everywhere. That seems unlikely. Hence my question about, 'getting it in writing' from the manufacturer, and not just a verbal reply from whoever picked up the phone that day. I had a related experience which illustrates why we need question such'experts'.
My old Craftsman Snow Blower had peeling paint and rust from the moment i bought it. After calling Sears I ended up at MTD, the actual manufacturer of the machine, and lady handling their 'tech' calls. I explained the problem, and she began questioning me about the use of the snowblower. I suspect she was reading from a computer screen. She asked if I had allowed the machine to, " Get Wet", as that was one of MTD'd prohibitions that might cause the rust and peeling paint problem on my new machine. After a moments hesitation from this remark, I pointed out to the lady at MTD that we were discussing a Snow Blower, a machine designed to dig into and throw what was essentialy water in its solid state, and therefore Not Getting It wet, was never going to happen. She called her supervisor after that and the conversation continued. You see my point ?