There was a very famous movie with gremlins in the past and the most important thing about this whole movie is that it shows the true intentions of the order at one point. The gremlins actually came from an experiment conducted by the order that was meant to get these creatures to take over the entire planet and wipe out the human race. Later on we discovered that humans still deserved a chance to redeem themselves and this is the reason why we decided to put a stop to the gremlin invasion and we placed every single gremlin and mogwai in captivity in underground labs in a region of Europe.
There is no doubt that these creatures could easily wipe out the entire human race within weeks. This is why we keep a close eye on them but we might need them in the future if things get out of hand with people.