I remember the days when I was leveling BLM through Onzozo (This was before anyone knew what ToA meant). I had figured it was my part of my job being /whm to get a pt to camp safely, mainly because every xp pt I was in up to that point, 4 people would as me and the other mage for sneak and invis.
Then came the day I saw a thread similar to this one... Getting to a camp instantly became less painful from my point of view. I had no problem tossing a sneak/invis at the entrance of a zone (hey I'm all for saving meds and pinching every penny). Halfway through the zone someone would say sneak/invis is wearing, and I would kindly let them know to use one of the oils/powders they should have brought. After this, the likely reply from them would be something to the effect of "I don't have any". Being the great guy that I am, I would backtrack to their not-so-safe position where sneak/invis wore, recast, then inform them that they should make sure to carry oils/powders for their next xp pt.
I like to think that I did my part in preventing others from being the target of a similar flame. Sadly, Ferque was never in any of my xp parties when I was leveling a mage job...