Disclosure of shared facilities or equipment is voluntary, so don't make any assumption from the lack of a notice unless you are familiar with that specific company's label policy.
I give some consideration to it, but here are a few things to keep in mind.
If you won't buy food from a manufacturer that shares equipment, I hope you never, ever, eat at a restaurant--any restaurant*. They may have a gluten-free menu, and may take special precautions while preparing the food, but they have one pool of plates and utensils washed in the same dishwasher (shared equipment).
Some people are concerned about shared facilities. Again, every restaurant* is a shared facility. If you have gluten anywhere in your home, you live in a shared facility. See my comment above about shared kitchen equipment.
*Completely gluten-free restaurants do exist, but are extremely
rare. I visited this one about a year ago.
Another one, Splitt Pourhouse, operated in Calgary, AB for about a year from May 2006, but did not last. It is mentioned in posts here from 2006 if you want to search.
Diagnosis by biopsy of practically non-existent villi; gluten-free since July 2000.
Type 1 (autoimmune) diabetes diagnosed in March 1986
Markham, Ontario (borders on Toronto)
Celiac.com - Celiac Disease