I did start out saying I simply do not believe them. They don't have data from the time they were down, presumably. That is a big hole in the data for one instance.

>assuming they don't do basic sanity checking.

I'm sure they have a million ways to say its not my fault. I started writing a huge response about human nature and the incentive to massage stats but I think you will dismiss it. If a system is down its a great opportunity to get a blame hedge in case sales are not as good as you predicted. There is no incentive to take an honest look if a brief downtime really affected sales in a meaningful way. I doubt anyone even does look. They just say this it what it would have been in our models if the downtime did not happen.

dunning-kruger