You're right, I wouldn't say your grocery store is an advertising company because they put Crest at eye level - I'd say they're an advertising company because they likely sell your loyalty card data to 3rd parties for $$$. Adtech is eating everyone's data.
IDFA is still going strong on Apple phones and is likely to continue into iOS 11.
IDFA is still going strong on Apple phones and is likely to continue into iOS 11.