Complex sentence: The Weavers avoided the more controversial songs in their repertoire, as well as avoiding performing at controversial venues and events, and the leftwing press derided them as having sold out their beliefs in exchange for popular success.
Split into simpler sentences: The Weavers avoided recording the more controversial songs in their repertoire, and avoided performing at controversial venues and events. The leftwing press derided them as having sold out their beliefs in exchange for popular success.