Actually, the world _does_ stop turning because it's Sunday. Anything happening on the weekend is emergency management, which takes time to scramble. I work in network/information security, and if we had a security incident on a Sunday, it would go to our backup team (of one). If they (he) deemed it critical, they would notify the security director, who would notify my boss, who would notify the rest of the team. This would take 3-5 hours, plus the amount of time it took us to get to the office and actually investigate the emergency. While we were investigating, we would likely shut down everything (including user accounts that were involved).

Weekends are time away from the office. I don't understand how you could expect the same amount of service on a weekend opposed to a week day. Do they deserve to be commended just because it was a weekend? Internally maybe, yes, externally maybe not. Fact remains that the weekend is when they are most likely to be short-staffed.