Firstly, everyone understands the difference between healthy sleeping/eating versus sloth and gluttony. Everything in moderation right?
Secondly, you confuse ego with self-importance. A poor ego doubts itself and may never attempt a daunting task because of the belief one is not 'good enough' to complete it. This becomes a convienient excuse to avoid doing difficult (but worthwhile) tasks. A healthy ego will undertake challenging tasks, because failure (in the traditional sense) is ok - failure will not define you as a person. The success comes from learning along the way.
Thirdly, we all have to do trivial things. This is a fact of life. However, how many times have you focussed on non-essential details in a project to avoid the meat of the thing? Its a common form of procrastination I catch myself doing. You also see it in overstuffed corporate environments - the term 'busy work' comes to mind.