There are several synonyms for the phrase 'are wasteful.' These may include 'squander,' 'waste,' 'deplete,' 'burn,' and 'fritter away.' These words express the idea that something valuable is being lost or used up carelessly, without any thought for consequences or future needs. Other related terms might include 'extravagant,' 'unnecessary,' 'excessive,' and 'superfluous,' which convey the notion of overdoing something or taking more than one needs. Whether we're talking about resources, time, money, or energy, the idea of wastefulness implies a lack of awareness or concern for the impact our actions have on the environment and others around us.