EDIT:
Carlove1
I liked your list as it made me feel slightly better for being a miserable git! As i get to order in fish by my choice and sell them too, your list kind of proved my thoughts too...
The same should happen with Clown Loaches, Bala Sharks/Silver Shark, Blue/Gold Gouramis, Kissing Gouramis, F8 Puffers, Common Plecos, Angelfish, Oscars, Neolamprologus, Chinese Algae Eaters, GSP, RTBS/Rainbow Shark...
Clown Loaches.... as soon as someone mentions them i say... "do you think 3+ 40cm fish would be happy in your tank?"..
Silver Sharks.... See that group of huge ones in that tank down there?.. see that poor bug eyed tiny bent one?... thats what happens...
Blue/Gold Gouramis... bit of a funny one, get big and pretty aggressive but at the same time,i've seen a lot of incredibly peacefull if not timid ones!
Kissing Gouramis... i just wont sell them...
F8 Puffers/GSP... i got so sick of unsuitable customers that i stopped selling them...
Common Plecos... I refuse to buy in small ones but I take in large plecs to spare them... regularly refuse to sell them... daily
Angelfish... big bugbear... a adore angels! The are beautiful devilish fish! I wont sell them to under 200L and i will press how aggressive they are and how if small neons etcare added.... they WILL eat them... etc
Oscars...urgh... shame... im sure they are nice fish but working in the industry... all i get to see is they poor deformed beggers with hole in the head... I wont buy them, give credit for them or sell them if ican get away with it. Got to be the most abused fish along with common plecs!!
Neolamprologus... not entirely sure what your problem is here??? Im pretty sure shops selling malawis to communities are worse!
Chinese Algae Eaters... REFUSE to sell them... same with most species of garra... i just wont get them in... why would i? I may as well give in and stock all the above and a few pangasius and red tail cats for the fun of it!
RTBS... i think i must be a rarity of a shop to refuse to stock them... they are a gorgeous fish in the right hands... if customers bothered to do even the smallest ammount of research first and had a tiny amount of respect for people working in the shop and their advice... i might have them in.. but i got so sick of customers DEMANDING i sold them one... ignoring advise and if ihad them there and refused to sell one... they would go elsewhere and get one from certain big chain store with no ethics. I found if they werent in the shop... less people asked and it was a lot easier to offer alternatives and explain why they couldnt go in the tank when they werent there tempting the customers!