And, Bayn, the new players aren't getting PK'd by the quest mobs because PK stands for "Player Kill", instead they are getting vicariously SK'd (Seer Killed).
But, on a more serious note, most of the invasions seem to be happening in towns that are not frequented (as much as, say, Britain) by new players. Everyone has to know they take a risk when they venture out into the world. Yes, even Britain can be dangerous from time to time (and kinda often lately, huh?) but for the most part it is the safe haven of the shard. After all it is the seat of the throne and should be well guarded and safer than other towns most of the time.
Players should know they take a risk when they venture outside Britain. If they don't know that, then sooner or later they will learn. I think that is one aspect of these quests that people don't often think about-- it is often a learning experience.
At any rate, death taxes are usually small for newer, weaker characters and they may find themselves being rescued by a large band of hearty warriors and mages and swept up into an exciting adventure! And at the end of it all, the chances are good that they will receive a good share of the loot (if not all of it, in the case of a rescue) to pay for their taxes. What could be more fun?
Crafters are a different matter, and may be gimped if the player has crammed too many crafting skills onto a single character. That's their choice. There is a reason the Trade Skill is not part of your Primary/Secondary skills--so you can have a viable character and still have a GMed trade. Still, crafters may be gimped in other ways because they may choose to add other skills to supplement their crafting. A Blacksmith might want Mining too, for example, or a Fisherman might want lockpicking to open all those chests they find. Again, this is a personal choice. If, as a crafter, you don't feel up to serious fighting, there isn't any reason you can't join up with other crafters chop wood, or mine, or fish, or whatever--and have the extra support of their company. That still doesn't help much in towns, just going to and fro, but like I said above, that's the risk you take outside of Britain!