My response is, "Great". "Now you'll have a better chance of finding a record of them!" As we search for ancestors a little farther back in time, we are usually limited to church records of births, marriages and deaths and often have little other information about their lives. That is 'unless' they were in trouble with the law, government or society. Then their misdeeds are usually recorded in records that still exist today.
In my own lineage, my 10th great grandfather was hung for murder. Another was banned from his colony for getting his girl friend 'with child'. Others fought against the British Crown in Scotland and in early America. Several were given some of their inheritance and told to not return home again because of their wicked ways. Three of my ancient grandfathers were drawn and quartered by the British after loosing battles with them in Scotland. Many, many of my ancestors were forced to leave their native countries because of their religious beliefs.
A large number of my ancestors were hero's in battle, in statesmanship and in leadership rolls. Do I honor them above my "Black Sheep ancestors?" No, I don't. They are all people, who lived their lives and for better or worse impacted the lives of their families and many other people around them. I am proud of those who did their best, exhibited their bravery, wisdom and honesty and I often refer to them when teaching youth and others about making the right choices for the right reasons.
The actions of my "Black Sheep" ancestors actually allow me to find information about them that I'd never find otherwise. Without their 'nefarious' crimes and actions, I wouldn't have any details about them other than a name, some dates and some places. Except for the murderer, few of the crimes they committed would even rise above the norm in our society today .... but that is another topic.
Don't be afraid to research your family tree because you may find someone who didn't conduct their lives like you do, because invariably you are going to find them. Everyone has them in their ancestral tree. Learn from their mistakes and remember that strictly from a research standpoint, the 'rounders' in your family may have left you the greatest set of tracks to aid in your research for their entire branch of the family.
You may even consider joining the International Blacksheep Society of Genealogists to see if other researchers have found information on your ancestors as well as sharing the information you've discovered about them.
If we don't keep our own noses clean, one day we may be one of the Black Sheep in the ancestral tree of our descendants or conversely, we could be the ones with 'gold stars' by our names because of our exemplary lives.
Whatever you find in your family history research, be grateful that you found a little more about lineage and that your perspective of how you fit into the weave of your ancestral quilt is enhanced with each discovery.