system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do ice cream trucks have really unique and cool ice cream treats, while the grocery store has almost none?

Whenever an ice cream truck comes around, they have awesome ice cream treats: ninja turtle stuff, mickey mouse stuff, spider man stuff, sonic the hedgehog stuff, etc

A quick google search of "ice cream truck ice creams" gives a slurry of pictures of what I'm talking about. However, when you go to the grocery store, none of these awesome ice creams are anywhere to be found. 

Why do ice cream truck drivers have this huge variety of awesome treats, while you're lucky if you grocery store has anything cool?
gpt
For the same reason as if you went to a Mexican restaurant, you'd find far better variety of Mexican foods than if you went to a diner that happened to serve tacos - It's a specialized endeavor, bringing people in with only one thing in mind - Ice cream and related frozen treats. It's not feasible for a grocery store to stock 40 different types of ice cream bars - tons of stuff is going to remain unsold and eventually wasted. They stick to the highest-volume sellers which for grocery stores, aren't Ninja Turtle Freeze Pops.