Which version were you playing (Windows/Mac/Linux/Web)? The game goes to a new "round" every minute (indicated by the countdown timer that appears on most screens). At the start of each round, 0 to 3 new pieces of broken pixel art are generated, but if the store is empty, then at least 1 should be generated.
Was playing the Web version. I didn't notice a timer anywhere. I can't say for certain but I'm almost positive I was playing for longer than a minute.
OK, so I found the problem. It was a bug specific to the itch.io production build where the game didn't initialize the game's save data properly the very first time the game was run. It could be circumvented by simply reloading the page, but I patched it so that it shouldn't happen now.