This video from the USA says about itself:
9 January 2017
Several Palm Warblers hunt for insects in spiders‘ webs in the morning – just like going to the grocery store! The spiders do all the hard work and the Warblers wisely reap some rewards. This behavior has apparently not been too well documented on video, although there is a technical name for this that I just learned – Kleptoparasitism (a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food). Always something new to learn by observing Nature!
Here is a link to a short scientific paper on the subject.
See also here.