My experience is that on the low-pop shards, my fellow Trammies rarely run into raiders at champs - but when they do, they're almost always cross-sharders who were there to farm scrolls to take to Atlantic, and didn't want competition.
The simple fact is that the manner of drop for PS means that it's near impossible for most players to get the specific 120s they need from champs in anything resembling a timely manner. That means they have to buy them, or take 3-5 years at least to get them the hard way. When PS were sold on my shard, I at least had an option (and it took 4 years to save up gold for a 120 Magery, because other expenses meant that I barely had more weeks with a net gain, than with a net loss). Now, PS are pretty much only sold on Atlantic, furthering the imbalance.
I understand both sides, but I get the distinct impression from the arguments that more on the pro-shardbound side understand both sides, than on the pro-transfer side (where most of the arguments seem to assume everyone has several platinum in the bank, and the ability to use shard shields at will)