Or am I being too pedantic? 
The school newsletter usually has a few typos, but this week the head teacher's letter but had about 8 comma splices. I winced every time.
Wibu to email her - we are acquaintances out of school - and let her know in a friendly way? I don't know if the office staff type it or she does...
Examples are
We love learning in our school, this week I was delighted to see x and y...
I hope you enjoyed the Xmas service, many thanks to the vicar...
Thank you for all your cards and Christmas gifts, we do appreciate them...