eComXpo - If you're "different" don't bother

I was pleased to get a complimentary "pass" to the online exhibition and was looking forward to hearing Seth Godin's speech this week at eComXpo - until I received this little notice via email:

We would like to thank you for registering for the eComXpo show to be held October 6-8. We noticed that you register using the Mac Computer. Please note that access to the eComXpo show requires the use of a Windows PC and Internet Explorer version 5.5 or higher. We want to make you aware of this ahead of the show so you can prepare accordingly to access the show and enjoy the Affiliate Marketing experience.

Just a guess, but wouldn't it safe to assume a fair amount of what's being done "on the edge" these days is being done on Macs?

I am disappointed and even a little bit ticked at Seth for offering me something I can't use.