Everybody I know whose fish got ick from feeders, keeps a constant supply of feeders in their tanks.
Everytime my tanks get ick, it's from old fish beating up brand new fish.
I would rather my fish not live to be 20, but be able to eat live foods. A lot of customers who feed their piscavore fish strictly pellet/frozen food diets that trade their fish into our store have very weird fish who tend to sulk 90% of the time and do not act personable.
maybe they are sulking and non personable because they are stressing from abandoment... they do not take to change very well especially to LFS store.. where tanks are small and lights are on all the time and people and movement constantly..think how you would feel. And granted...fish who are fighting and under stress tend to get ick .. only because the ick was there.. ick has to be in the tank for fish to get it.. and weakened fish will get it sooner and more often..