For me it is probably feeling hot most of the time, sweating too much and the aches I get in my back and knees when I have been standing for too long. However, overall I have no complaints about being obese. I would recommend it.
As above, it's being hot and the swearing. I mostly wear performance fabrics now that wisk the moister away. I can't stand heavy non-breathable fabrics. I would have to say, second would be the difficulty in Butt cleaning. I have just about given up trying to take care of my feet myself. Just too much work!
Sometimes the choices you are forced to make as a result. Do you part/distance yourself from longtime friends and family who want you to be "healthy"?
Learning when to pick and choose your battles. Like the same people who look at you in disgust for taking up 2 seats on the train/bus, look for you to help when crazies/thugs start harassing them.
Deciphering if people are "attracted" to you or if subconsciously; you remind them of an obese father/uncle, mother/aunt/cousin who reminded them of a simpler time, a better time in their life before they passed on.