you should have paid attention.
proper flag retirement involves cutting the fabric apart first, typically separating the colors along the seams, but sometimes as simple as cutting the flag into four equal pieces, so long as the field iof blue is left intact to retain the symbolism of a united country of individual states.
once the fabric has been separated, it is no longer considered an American flag, and burning or incineration can be done.
The ultimate goal in any of this is respectful handling and intent. Unlike the "f yo flag" videos from five years ago, I guarantee that the retirement event you reference was respectful. Ask a member of the VFW or the military, if you can when stand to be in their presence. Ask a Scout. I've taught this to them for years.
"Burning is burning" is not true. you may sit down now.