All interactions where someone doesn't have a choice in the matter.
Someone needing emergency healthcare doesn't get to pick which staff they'll interact with.
Someone having a fire emergency doesn't get to pick who will respond.
Someone needing the police, or more importantly someone having the force of law imposed on them doesn't get to pick which officer does it.
It would be nice if public heath guidelines changed to require businesses to post if they require testing/vaccination or not. Just like health code and occupancy notices. Then, customers who have a choice about what businesses to interact with could use that information in the same way. "This business cleans correctly to deter rats and prevent food poison, requires hand washing, AND it's employees are tested regularly or vaccinated. Also, the dining room holds 200 people or it's fire hazard if there are more".
Doesn't change interactions with government services. The federal employee mandate deals with stuff like someone doesn't need to worry about exposure to COVID if they need to deal with the Social Security Administration or the IRS. Healthcare, fire, police, court systems, all fall into categories where people aren't given an option to pick a different business.