If it helps, I was looking at how much I could purchase potatos for from the Local Market so I slid the slider to the max and then lowered it to around 19 or so. When I'd hit purchase I lost all of my gold as if I purchased all the I could but still only received the 19 I changed it down to.
#Shop Bug
valid flax
valid flax
Update: I just built back up 60k gold, went to purchase a single Normal Bow for 1k and I lost all of my gold again.