you're right. Smells do trigger our memories. I was a child during the Great Depression. We lived in a shanty with no electric or plumbing. We heated with a fireplace and cooked on a wood stove. So those smells do bring back memories of a simpler, innocent time. Frying bacon always reminds me of my aunt.
There are times I'll smell something specific, and I'll go nuts trying to figure out where it's coming from.
Reason being that I've got memories flashing through my head like a horrible lightswitch malfunction and have to track the source of the scent to get the memory flashes out of my head.