RSVP? To What?

I'm so excited, I've been invited to a wedding! Or have I? Not the wedding itself, but the "reception" to follow it turns out - but it gets even better.

On August 4th, I received a mailing with the subject line: Theresa, I need your RSVP.

Okay, I bite, basically because I thought it was true. I read:

"Did you get the invitation to my wedding reception last week? Because I haven't received your RSVP yet..."

Yes, I did panic a bit at first thinking I'd overlooked a good friend's invite and... well you know that feeling.

Then I read on... !

Turns out I'm one of 1,500 complete strangers invited to this "well-known" person