You're forgetting how children's toys are sold.
Sealed boxes arrive at the store from the factory. The toys inside the box are not evenly distributed, they're proportionately distributed. Rares, middles, and commons, meaning that for every 10 kes, there will be 5 Janeways and one Seven of Nine in any one box of Star Trek Toys. If the shop wants 10 Seven of Nines, they have to buy 100 kes dolls.
What the hell is a baseball memorabilia shop in the boondocks going to do with 5 score Kes action figures on any day other than the fourth of July.
Detroit Rock City could have a field day with a Kes Army.
Speciality shops however buy collectible toys in full sets. No rarity or imposed scarcity, but because it's all made to order, it's a smaller line and therefore greater cost per unit to generate a smaller proportional profit.
Screw your passion.
If you want to make money, just sell cigarettes and whiskey.
(If however your passion just happens to be cigarettes and whiskey, kudos & mazel tov)