S.G.
My mom has Celiac & is 100% gluten free. I know she has problems if there is an accidental cross-contamination, but she's never had trouble with coffee. She orders Gevalia coffee specifically, but she also drinks what is at my house (usually starbucks) and has never had a reaction.
Some companies just can't claim gluten free becuase they haven't gone through the inspection process to prove there is zero cross-contamination. BUT, soemtimes you can use common sence.... what else does Folgers produce that contains wheat products??? I don't think anything, so you're probably good. Same with wine... I wouldn't buy wine from the same manufacturer as a beer, becuase beer has wheat, but most vineyards are wine only.
My mom has had some unpleasant surprises, like cream soda. She was sick for 2 days, who would have thought? Some is trial and error, but for the most part companies and manufacturers are getting pretty savvy to it. they've come leaps & bounds in the 2 years since my mom started gluten free!