The founding fathers never wore a flag pin or stood for the national anthem...
Obviously hated America
That's true, but they did prey and also went so far as to print a congressional bible for distrubition, as well as take oaths of office and pledge oaths to their individual colonies as well as the United States. I fail to see the point here, if someone in todays time period right , wishes to express a sense of love of country by wearing a flag pin or for that matter, singing the national anthem which didnt really come into being until the 20th century. Your talking though about how each generation celebrates or expresses their love of this nation.
At the start of each new Congress, in January of every odd-numbered year, the entire House of Representatives and one-third of the Senate performs a solemn and festive constitutional rite that is as old as the Republic. While the oath-taking dates back to the First Congress in 1789, the current oath is a product of the 1860s, drafted by Civil War-era members of Congress intent on ensnaring traitors.
U.S. Senate: Art & History Home > Origins & Development > Institutional Development > Oath of Office
On June 14, 1777, in order to establish an official flag for the new nation, the Continental Congress passed the first Flag Act: "Resolved, That the flag of the United States be made of thirteen stripes, alternate red and white; that the union be thirteen stars, white in a blue field, representing a new Constellation."
USFlag.org: A website dedicated to the Flag of the United States of America - Evolution of the United States Flag
I see nothing wrong at all with how people of different generations celebrate their love for this nation and frankly, wearing of pins, or buttons, is as old as the Republic itself and because someone chooses to do so does not make it a requirement for others to.
My God! How little do my countrymen know what precious blessings they are in possession of, and which no other people on earth enjoy! ~Thomas Jefferson
Patriotism is not a short frenzied burst of emotion, but the long and steady dedication of a lifetime. Thomas Jefferson
Patriotism is as much a virtue as justice, and is as necessary for the support of societies as natural affection is for the support of families.
Benjamin Rush, letter to His Fellow Countrymen: On Patriotism, October 20, 1773
Point is I think that the Founding Fathers would be quite familier with celebrations of patriotism and love of country in things such as the national anthem or wearing of flag pins and would also defend those who choose not to. Thats the real beauty of this nation.