So far, in situations where it wouldn't be rude to ask, I've been able to determine with pretty good accuracy that at least someone in the household has the advertised health concerns.
You can also get an idea of their financial situation, given what buckets advertisers put them in and what they're advertised, as well.
Similarly, advertisers know when you're at friend's location, or elsewhere, and may show ads tailored to your profile.
- Signalling: I dress more formally than everyone else to make up for the fact I'm less professional in other ways
- No signalling: I dress like everyone else because I am like everyone else
- Countersignalling: I wear ratty old clothes with holes in them, and nobody will dare to question it because I'm the important one here
Or maybe you just can't assume you know what's going on inside someone else's head.