I will happily address your main point in a moment, but I do want to make a very sincere, respectful comment about what EfU is intended to be all about.
It is intended to be about something very intangible that we on the DM staff call "Awesome." "Awesome" does not come from rules-lawyering or getting-OOC upset about IC setbacks - although certainly we have rules that the DM staff must enforce in the interests of fairness for all.
"Awesome" is something rather more subjective. Allow me to provide some examples.
Playing a ballsy, non-FD'ing bandit that targets high-profile merchants with vastly superior levels + loot in the presence of other PCs (including Watch PCs), thus giving multiple factions something tangible they can work on (tracking down a criminal) along with the entire rest of the playerbase (bounty hunting, allying, etc. etc.) and just generally producing all kinds of RP = fairly awesome
Role-playing a furious merchant that's outraged over being robbed, and goes on to hire bounty-hunters to bring him the head of whoever robbed him while levying political clout to increase the security in Upper = potentially awesome
I think this is an opportunity for me to remind anyone reading this that the purpose of this server is not MMORPG tread-mill style loot/XP acquisition, but provide excitement and interesting stories for the playerbase, whether winning or losing. We are all just playing a game here, but the form of entertainment that we provide may well not be to everyone's tastes, and it is the business of every player to decide if we are the kind of server they enjoy, or the kind of server they do not enjoy.
Now, to address this specific question, and the rules regarding it.
"Ninja-looting" is generally defined as looting in a situation in which the character that is doing the looting really has no business doing any looting, as the PC has failed to earn it in any way. An example would be invis-stealth snatching-things up after another PC gets killed by a NPC during a laggy DM event, or clicking all the items in a dropped pack during some kind of arena event. So, a situation in which a bandit beats someone up, and then takes their gold, would not really be considered "ninja-looting" on EfU.
There is also the question of the plausibility of looting people's packs during combat. Beggar did write in a post say that he has seen examples of characters looting packs during combat that didn't seem plausible to him. I would agree - plucking multiple sets of fullplate out of a pack while someone is swinging at you is not very plausible. However there is a very real difference in terms of plausibility between picking up tons of heavy loot and spending more than a round (including time spent emoting) in plucking up a coin-purse, however heavy it may be.
So, in this situation, I would say I really see nothing implausible or illegitimate about what happened, although the lag and pack-unresponsiveness certainly complicated things, but that is a separate matter.
I hope this clarifies this issue, and a reminder to all: Sanctuary has many banks!