I worked thanksgiving this year, Easter last year and we'll have a few guys working Christmas. There is no off limits days. I always marvel at the customers that say "I can't believe you guys work on Easter" and I always say "I can't believe people request appointments on Easter"
It could be that they all don’t ‘request’ the holiday. Probably when they call the salesperson says ‘we have an appointment available tomorrow’ etc... They probably just figure what the hell, I’m off work so I’ll be here and I can get it done.