Not specific to Canada, but in general:

Yes, you are overthinking. The main point is: nobody wants your sweat-drenched dusty worn textiles. Or your scratched-up old helmet. Especially in a small community (in the middle of a big city people vandalize it just out of generic spite).

Gloves into helmet, helmet on the side of the bike (either underseat hook or a convenient piece of crashbar/rack carrier tubing), and it's secure enough to leave for a multi-hour hike. Your worry is not thieves, your worry is rain getting inside the helmet or wind knocking it off, so don't just leave it on your mirror as you would for a short stop.

Pack up your riding gear and boots and stick them under the packsafe net, and you'll be fine. Alternatively, I've actually walked into the visitor center of national parks and asked if they could keep my suit and boots under a desk for a few hours.

Probably pretty decent, but understand that you might be abusing the natural hospitality of people who live in communities where lack of hospitality is a threat to life.

If you roll into a village and ask the local guesthouse if they have a bed available, they will probably figure something out even if they're full up - because they are problem-solving within the bounds of their job.

If you roll into a place where there is no guesthouse, but you just ask at the pub, they will find a local to give you a roof over your head, but then you are forcing people to go out of their way on your behalf, and it's bad karma.

I would do some research in advance and plan my route so that a place with commercial accommodation is always at least available nearby.

Don't use up all of the storage space on your bike. For me, the topbox is always empty while riding. It's for me to put the helmet/gloves while I am off the bike, and my day's food shopping when I am on it.