Again:
1) There are literally hundreds of other bakers they could have gotten their cake from.
2) There is no proof that homosexuality is a natural, genetic, inborn or otherwise natural basis for its existence to be protected, and I've cited the studies repeatedly. Until at least 1973, and in many parts of the world the 1980's and later, it has been diagnosed as an obsessive disorder, like pedophilia, sadomasochism, foot fetishism, gambling or substance addiction. And in many places, 10 to 20% of psych professionals in the U.S. who belong to NARTH,
still is treated as a disorder.
3) Religious freedom.
You don't force Muslims or Jews to eat pork.
You don't force Hindus or vegetarians to eat meat.
Again, if gays had just wanted a birthday cake or a cake for some other holiday or event, the Christian bakers would no doubt have gladly obliged them.
They only exercised their freedom to not endorse
this specific event.
4) The first Amendment:
Congress shall make no law respecting the establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press,; or the thright of people to peaceably assemble, and to petition the government for a redress of grievances.
Learn it.
LIVE it. 
The problem with gay Nazis is they think that only they have rights to free speech, and that anyone who disagrees with them should be silenced. It doesn't work that way.
Gays have a right to their beliefs and lifestyle, despite those who disagree with them.
Christians have a right to their beliefs and lifestyle, despite those who disagree with them.
You really need to learn to respect the beliefs of those who tolerate yours.
