Is that an error?
I like to share with you about an email that I received. I thought that its really funny. As mentioned in the email it written " I will like to invite all of you ". What do you think of this means? Its very clear saying that the invitation is inviting everyone right. If you didn't finish read the email you will not seen the "restaurant is relatively small, we should limit the number to maximum 4 per family."
I do hope who ever that received the email will read through it and not thinking that the invitation is for everyone. This is like a human error which easily get people misunderstanding.
This reminds me of a friend who telling me that her aunt has an open house and just wanted to invite sisters over for small gathering. Who knows her aunt's sisters started calling son-in-law and daughters to join. I don't think there's anything wrong. But I would say that if you want to invite somebody tell them clearly that how many of you that you are inviting. If you just want to invite 1 person just say it!