Cancellation of Santa Day

My husband’a side of the family have taken upon themselves to do a Santa Day for the kids in the backyard. We all have said we are looking forward to it and the kids can’t wait to meet Santa! Suddenly, our uncle texts if it’s best to cancel due to Covid! First off, we are within the appropriate regulations so I don’t see what the issue is. I’m annoyed that this is now being considered to cancel it all after getting these kids worked up. They did the exact same thing last year, but was rather more appropriate because we weren’t vaccinated. I haven’t responded, I find it really crappy to pull this last minute