is there anything we do now that will be considered CRAZY in the future?

Practically everything.

Humans continue to fight nature, even today. Before it was thunders and rain, now it is the dehumanization caused by technology. And many low human instincts continue to exist. It is necessery to make an effort to keep some sense of "owning" over circumstances. In the 1800's Britain gave birth to dandys. It was no longer about dominating the World, the new religion was aesthetics. This gives you an idea of the efforts that is possible to establish in order to not loose yourself in the circumstances.

Yes. Driving to work, filling the highways with bumper to bumper traffic, and polluting the air with gas emissions. The atmosphere might even be so bad that it might be considered crazy to even go outside. I envision indoor cities built to some extent like huge malls but with all inclusive living communities with artificial sun and tracts for agriculture. Food will be compressed and dried and we will meet our nutritional needs with tiny portions of very filling dried foods. Carrying cell phones will be a thing of the past. We can wear hearing aid type devices that serve as phones, music players, and computers all in one. Monitors can be affixed to eye glasses and produce an effect very much like a large monitor. Clothes will be self cleaning and adaptable to any environment with chameleon like camouflage capabilities. I have more but I'll save it for the book.

Working for a living!

Perhaps heterosexuality and homosexuality.

As minds evolve to be more open-minded and free, one could argue that people may learn to accept the carnal pleasures of other human beings no matter what gender. Especially with plastic surgery technology improving, gender changes happening, media becoming more lenient and generations getting more and more sexual at younger ages.

Not that I'm bi!

In the early days different religions carried out sacrifices ( animals, plants , various material stuff and humans) now we think they were crazy. The futur generations mite think religious practices like going to church and praying crazy.

I think the wiser people are the more they will comprehend how and why earlier people were more primitive, misguided, and out of control. Similar to the way we as adults comprehend the simpler view of life which a young child has.

I feel that in the future, these times will be looked back upon as the dark ages. The first few subtle rays of Dawn....but nevertheless the dark ages.

Failing to recognize that overpopulation will be the cause of the collapse in our society.

War.