Should service of process protect privacy?

I used to work for a law firm; we always gave the process servers paperwork to be served in a sealed envelope to protect the privacy of individuals.

This doesn't happen now. Is service of process somehow exempt from providing a reasonable right to privacy? My neighbor was just served yesterday, although only his sister was home at the time. Apparently it was to advise him of a judgment, and an attached affidavit showed his name, (unlisted) phone number, and social security number. None of this was in an envelope, but available for anyone to see.

With identity theft becoming such a common problem, this certainly isn't a wise move. I can't see that it is ethical, but is this method of service really legal and approved?

For what it's worth, we are in Mesa, AZ. The company trying to collect is apparently not reputable, so he's fighting this. I don't have the resources I did, so if this provides additional ammunition, please advise! Thanks!
Answer:
In many states service is ineffective if it is in an envelope.

---

In CA where we serve process all legal papers must be plainly visible to the person being served. It protects us so we know EXACTLY what is being served and keeps us from being hauled into court by people claiming a certain document was not served and wasn't in the envelope.

All documents for service have the originals in the court file in the courthouse. All you have to do is head down to the court pull some files and you have all the info you need.