
3 goblins, who happened to be very good at alchemy, made a great many number of poison and antidote potions, and brought them to big city to sell.
They rented a place on the local bazaar, and put up 2 vendor signs - one for Poisons, another for Antidotes.
Unfortunately for them, the business was going very slowly - no one wanted to buy from goblins.
Then goblins decided to be tricky. They crossed out one of the signs, and wrote two words over it... By the end of the day they have made a great deal of profit.
Question: what did the Goblins do?

PS. If you know/figured answer right away, don't post it right a way - give others at least 24 hours to figure it out

