Why doesn't the accused get a right to a jury in all situations?

Why doesn't the Sixth Amendment to our Constitution guarantee a right to trial to citizens of felonies of under a year, or misdemeanors? After all, this is what the Amendment states:

"In all all criminal prosecutions, the accused shall enjoy the right to a speedy and public trial, by an impartial jury of the State and district wherein the crime shall have been committed, which district shall have been previously ascertained by law, and to be informed of the nature and cause of the accusation; to be confronted with the witnesses against him; to have compulsory process for obtaining witnesses in his favor, and to have the Assistance of Counsel for his interpretation."

This is not open to interpretation. If accused of a crime, no matter how minor of a crime that it might be, you have a right to an impartial jury. The size of the jury is not stated, so it doesn't necessary have to be 12, it can be just a 3 member jury, but you have the right, nevertheless. But summary offenses don't require a jury trial, for some reason. For example, if one is accused of contempt of court, you can be tried by the judge himself, who charged you. That seems to be a clear conflict of interest.

A misdemeanor that results in no jail time does not also guarantee a right to counsel under the Sixth Amendment, as courts have held. But a misdemeanor is a criminal offense and prosecution, why is that not protected?

Also, should infractions be considered something where a person has a right to a trial? They don't care jail sentences, or probation requirements but do extract a financial penalty.

In Nevada one does not have a right to a jury trial for a misdemeanor where the charge is considered petty. By the way, the punishment for a "petty" offense can be imprisonment up to 6 months. Hardly petty of course.

Oh by the way, there is no right to a jury trial, for juveniles, even if tried for a serious crime that involves being locked away for every years, if charged as a juvenile. So in effect, they can get the same punishment of a low level felony charge, but with no right to a jury. It was even worse before 1967 though.

So, when someone decries so called "judicial activism" they are probably a person who doesn't want the courts to protect in the least the rights of Americans. They want a watered down judicial system that ignores our Constitutional rights.