The problem here is poor communication. The way I read the letter, the raid leader and the letter writer had different ideas about the loot rules, even though they thought they understood each other. The letter writer was told s/he wouldn't get anything unless nobody else wanted it and therefore put in a /roll for any items that would be upgrades, but didn't bitch when the items were rightfully handed over to the guild members. The raid leader, however, seemed to take offense at the act of rolling on loot itself, despite the fact that it wasn't awarded.

In my guild, I have no problem with people who roll on every piece of loot that's beneficial to their class, as long as they understand that they will not be receiving everything they roll on, or perhaps receiving nothing at all. In fact, I encourage people to roll. I need to see who is interested in and can use an item before I check to see who deserves it according to our loot rules. I try to make this clear to my guildmates, but sometimes it might not come across.

Long story short: the letter writer may well have offended the raid leader with his/her rolls, but the leader obviously didn't communicate the loot policy effectively.