I maintain that the sentence shows no disrespect to my Midwestern sensibilities. It's considered common courtesy to ask someone how their day is going, and I don't consider "you guys" to be a sign of disrespect. In fact, it seems quite clear to me that the parent was attempting to be warm and welcoming.
Warm and welcoming sure but too casual, you guys IMO implies familiarity, I wouldn't use it with strangers, could be regional or generational but that's my rural Illinoian take. Y'all is more flexible.
I agree with the other poster. Missourian and "y'all" is ridiculously less formal than "you guys". To me, "y'all" is specifically informal and is used in exactly that manner, even in corporate emails. It denotes a more conversational tone that's open to feedback. "You guys" does not exist within formal/informal for me, it's either, neither, or both, just depending on what you say around it.
"How are you guys doing today" spoken at a red lobster is absolutely fine, completely normal language, whether spoken by the president or by a child. It's the single most ubiquitous and wholly normal greeting that i know. Corporate really over does it sometimes
Fascinating - I'm from Michigan, and I would say "y'all" sounds more casual to my ears than "you guys." Formal speaking (in contrast to casual speaking) often eschews contractions.
That manner of social formality set sail a good 25 years ago my friend. On one hand I find it a shame, it was useful, on the other, it was also often misused (still exists in Korea where I now live, and it's abused like crazy here).