Ugh, the first time I came on a kecleon shop was in red rescue team. It was Mt. Steel, I had been doing amazing and I saw the shop. Not knowing what it was, I stepped on the oran berry and pressed "eat". The kecleon warped (which scared me like heck) and asked if 200 poke was acceptable. I accidentally pressed "No". Then thousands of kecleons popped up and I was murdered in two seconds. Ouch.