I think it was a smart business decision on Turbines part.
For years many of us have been asking to change Bound to Character to Bound to Account for all that lowbie gear we grind for, just to level past it when we get it, so now that once treasured item sits in a bank slot, unused, but yet unsold, as we just can't part with it. How many times did you have to run "Splinter Skull" to get your Crimson Gemstone? I know most of my casters had to run it many times to get it, just for it to be discarded around lvl 9. Now I can give my new Characters the old gear without having to run the quest 10+ times to get it, via the shared bank slot.
F2P people do not get the shared bank slot unless they buy it, so they cannot share Bound to Account stuff with new toons. This increases the value of an item that to me is already one of the most important non-content parts of the game, the shared bank slot, and at some point, after my F2P account has unlocked most of the content, It will be on my list of things to aquire.
As for the direct question asked, I do believe most of the good lowlevel gear and such that are desired do come from quests that are not F2P. So if you can get a Ring of Feathers, Cloven-Jaw Warbeads, Puzzlers cap, etc.. from the AH or trade, why would you purchase the STK pack? (I would and did because I like the series, but it certainly wasn't a "must", as there is plenty to do at that level) So yes I think it was mainly changed to encourage Pack Purchases.