I made a sin about 3 months back mainly for spots of farming ( punchout etc ) and to learn a profession i never managed to get used to ( skill chaining im weak on lol ).
As with any prof buffs that give an advantage you'll get ppl jumping in to make an easy buck - ursans/55's and so on.
Yes ppl hate ursans due to no skill required to use ( read the threads lol ) but the sin hatred has been around longer and specially in ab but as its already showing too many ppl ecto farming and selling to merchants is killing ecto prices.
And you get ppl rushing out and unable to buy the runes ( and complain ) or get bad bohemoth spawns ( and complain ).
Anet may put in some new anti sin traps and then we'll see uw sins crying thatuw been nerfed lol.
My sin dont do uw but farms thruout gw but we are also mainly solo farmers and who really wants to spend most of their time solo in gw - isnt gw aimed at party
I also team farm as sin but as a normal sin - more enjoyable.
And yes perma sf runners are usefull but ive only ran myself and a few guild members to droks etc and trying to be a pro runner has no interest for me , id rather farm and have fun than doing droks run several times a nite.