In Canada, Zebras that are around a few inches run for $500 and up and up, I;ve even seen them sell for $700 dollars in Toronto. Smaller specimens with their egg sacs still attached (baby zebras keep sacs for several weeks) sell for a $250 or more, but at that age are still susceptible to loss.
Price is important. If someone has money to buy them, chances are they have the money to buy more, and breed them. They are being bred in captivity, and a higher price means less people will buy them as single show specimens for their tank.
I work at the store in Burlington that was linked above:
http://www.hdas.ca/main/index.php?topic=777.0 They are absolutely gorgeous. By far the most beautiful pleco imo. Pure white, and pure black.
The one in the photos posted above by "
Frostyone" is likely a King Tiger. They are nicknamed the PoorMans Zebra Pleco. Some of them are very white in the background but the banding is brown and much more intricate than the lines of a zebra. Those are instock if that satisfies too...
If someone wants a reference for the zebras from this source and same batch, just ask. We had someone come soon after they arrive to buy three or four of them.
Also, Zebras arent algae eaters in the slightest. They prefer much meatier diets. Frozen foods and carnivore pellets.