I drive 70 miles to my dealer. They know that, and they know I run a saw 40+ hours a week, not 4 hours every other weekend. I buy a saw there about every 2 years. A flash and a new coil on an Auto-Tune they would do while I stand by the bench, or am roaming the shelves to stock up on misc. supplies. Fuel line stuff, they would not. Maybe they would in the winter time though.
They tend to check the carb model, and the ignition module (5 different on 550s over the years), and then hook it up to the laptop just to make sure it is running the newest / best possible Operating System, basically. They might do that if you came in with a broken plastic switch and no other problem, just as an automatic service for their customers I believe. The last time my 550 XP was in (drum teeth wore out) they hooked it up, and said "oops, we already loaded in the newer programming last time" (smashed the clutch cover that time). The 550 hasn't really needed much maintenance aside from some bad luck externally, nothing to do with the saw itself.
They receive a parts shipment from Husqy - daily, and it is fairly rare that they don't already have a part you might need, though I am good at needing esoteric parts off clearing saws. Sometimes, those end up arriving from Sweden quite a bit later on.
On Monday mornings, they also receive 1 or sometimes 2 pallets of saws on repair contracts from stores without a service department, and/or a large utility contractor. People they don't know will be placed in the same line with the saws coming off those pallets. They have completely separate departments for saws and lawn tractors.
I'm not trying to make you feel bad about your dealer, just relating what it can be like to drive to a really high volume one. It's worth it. I travel a lot for my work, and I usually just ask a basic question when I am too far away from my regular dealer - "where do the loggers go around here?"
But smaller shops have routine long wait times as they assemble a large enough parts/supplies order (oil, etc.) from Husqy to qualify for free shipping. I believe it can be worth asking if you can pay for shipping to get a needed item outside of their next "re-up" on stuff. I believe with small shops and the Stihl supply chain, you are just going to pay for shipping, automatically.