correct me if I'm wrong, but shouldn't it be:
"Thanks Anne, for stopping by" versus "Thanks, Anne, for stopping by"?
Anyone who has studied a bit of Latin knows that it's a language with a gazillion different cases-- nominative, accusative, dative, genitive, ablative, etc. These cases can be found in all languages, but they're either difficult to see or morphologically invisible, as is often the case in modern American English. Example:
He brings the kid the ball.
He = nominative case (subject of the sentence)
the kid = dative case (indirect object of the action "brings")
the ball = accusative case (direct object of "brings")
Compare the above with German, where the cases are more visible because you have to change the articles to reflect changes in case.
Er bringt dem Kind den Ball.
Er = he, in the nominative
dem Kind = originally das Kind (the word "child" is grammatically neuter in German), but in the dative case, der and das become dem
den Ball = originally der Ball in the nominative, but because Ball is the direct object of the action (accusative case), der becomes den
Sorry for the grammar lesson, but my point is that languages have cases, and different languages show those cases in ways ranging from invisible to quite visible. Languages like German, Latin, Greek, and Russian often show differences in case quite clearly. English, by contrast, doesn't normally change the form of words to indicate variations in case.*
But there's one major exception: the vocative comma.
The vocative case is all about calling or addressing people or things. In English, we indicate the relationship between the speaker and the one spoken to by inserting commas.
Hey, dude. What's up? (Not: Hey dude.)
Annette, I don't get why you keep dropping vocative commas.
Dammit, Spock, I'm a doctor, not an astrophysicist!
Hear, O Israel!
Buy, minions! Buy!
The last example gives us a chance to see how the vocative comma is helpful. With the comma in place, we have a despot commanding his minions to save the economy by shopping more. Without the comma, we have a despot (or somebody) telling some unknown person to go out and buy him (the despot) some minions:
"Buy minions!" = "You! Buy some minions for me!"
It's possible that the vocative comma may drop out of modern American English altogether, simply as a matter of "common usage," with people intuiting the vocative case through context. I'll be one of the holdouts, though; just as older folks still refuse to split infinitives (despite the fact that most current grammar and style manuals these days claim there's no damage in doing so), I'll be holding on to** those vocative commas until the barbarians come and pry them from my cold, dead brain cells.
In the meantime, I find it excruciating to read vocative locutions that lack vocative commas. I've seen "Hey Kevin" at the start of more emails than I can count, and it's all I can do to keep from weeping and smashing everything around me with a baseball bat.
As the "Buy, minions!" example indicates, vocative commas have their use. Instead of letting the barbarians erode the language further, take a stand and use the comma.
*For the purposes of this discussion, I'm considering the pronominal shift from "he" to "him" (or "she" or "her," or "they" to "them") to be so common as not to merit discussion. In English overall, very little morphological change occurs when switching cases. Beyond these basic pronouns, it becomes very difficult to cite examples of such changes. Only one other example comes to mind right away: the use of prepositions to indicate case, e.g., "She threw the ball to Clara." Clara is marked as the indirect object of "threw."
**Not "holding onto"! But that's a rant for another time.