Many of those who demand "acceptance" are quite fascist about it.
Take the National Association for the Advancement of Fat Acceptance, for instance. http://www.naafaonline.com/dev2/Founded in 1969, the National Association to Advance Fat Acceptance (NAAFA) is a non-profit civil rights organization dedicated to ending size discrimination in all of its forms. NAAFA's goal is to help build a society in which people of every size are accepted with dignity and equality in all aspects of life. NAAFA will pursue this goal through advocacy, public education, and support.
"All of its forms"? "In all aspects of life"? No, sorry.
This includes what I think about fat people. I am not attracted to them. That's just the way it is. In that sense, I don't treat them with "equality."
As for the rest, I "accept" fat people in that they are people and have the right to live the way they want.
But I will not tolerate them sticking their fat in my face, demanding that they be accepted and respected.
Another one of their tenets is to "improve the quality of life for fat people."
My opinion is that losing weight will improve the quality of a fat person's life.
NAAFA is of a different opinion. So it is a simple disagreement - and it is not incumbent upon me to change my viewpoint to accommodate theirs
NAAFA is only one example. Most "civil rights" and "advocacy" groups exhibit the same authoritarian streak.