flight rising is pretty much the only pet site i have experience with so i dont know any kind of decorum for pet sites

ive been picking up cheap G1s (listings for 15-20 gems) that I think are pretty and reselling them at a markup of 100-300 gems
but someone expressed to me that I'm being an asshole for doing that, and now I dont know and I'm worried that I AM being an asshole
i just wanted to flip dragons for some money :( so whats the general decorum for reselling shit?