Oh, playing tricks, huh?
Ceder chuckled as he looked at the stall owner before him, with their mysterious goods and obscurely impressive Rainbow Fruit, and that heavyweight rhetorical question, "It's very expensive, do you want to buy it?" Though the tone was plain and indifferent, it carried an air of disdain (purely his overthinking), irritating enough to make one's teeth itch.
This was simply the most common market ploy!
First, stir up strong emotions in the customer, make a mystery, then take the chance to peddle one's wares, selling something worthless for far more than its actual value.
Ceder had seen plenty of this sort of thing, so his heart was undisturbed, and combined with his fierce appearance, it gave the impression he could flip the stall at any moment.
"First tell me what you're selling," he said with a smirk, "Let's see what kind of treasure it is that can fetch an astronomical price."