Creelings generally avoid larger beings like humans, because of our propensity for picking on things that are smaller than us. In the past whole Creeling villages have been taken captive by wicked humans (and other beings) and forced to toil as slaves. Despite this dark history, there have been notable alliances between Smallfolk and "Bigs" as they call humans and others of our size. The Creelings proved to be valiant allies in the war against Malabron long ago, and they have remained friendly with the Tain Shee.
Creelings have a liking for the stuff that "Bigs" discard. They put our refuse and unwanted junk to clever uses in their building and home furnishing. Many stories have been told of the resourcefulness of Creelings, and the clever ways they have learned to live and prosper right under the noses of humans without us being any the wiser.
-- from Redquill's Atlas and Gazetteer of the Perilous Realm.