I've worked 8+ years in jobs that involve extensive contact with the general public.  In that time I've had to deal with a lot of insults and rowdy behaviour from people who were not too happy with me.  I thought I'd share some of the incidents:

Number One

While working as a security guard at a gun show I heard a knock on one of the fire exits.  Curious as to what was going on outside I opened it and looked outside to find a man and a young boy (his son I presume).  He wanted to be let in through the fire exit.  However, this was prohibited as people had to enter through the main doors and pay an entrance fee.  He claimed that he had paid already but wanted back in through the fire exit.  I declined.  He responded with, "To hell with you, you guys are assholes!"

Number Two

I was working as a guard and performing a patrol of some buildings downtown late at night when I found a guy standing up close to the back door of a bank doing something I couldn't make out.  So, I stopped the patrol car and shone the spotlights on him and got out to check on what he was up to.  It turned out that he was urinating on the door, most likely having imbibed a little too much that night at some downtown watering hole.  I told him that I didn't appreciate him taking a leak on the bank's door.  Then a police cruiser pulled up and an officer got out at which point the intoxicated man said, "Oh here comes a real cop! Your backup is here!" or something like that.  The police officer began to question him as to how much he'd been drinking but he ignored the question and demanded the police officer just write him a ticket so he could go home.  I guess the police officer didn't like his attitude because, instead of a ticket, he arrested him for public intoxication and took him to the drunk tank.

Number Three

While I was working as a trainee loss prevention officer (better known as a store detective) my trainer and I observed a woman steal over $100 worth of meat and stuff it in her backpack.  When we apprehended her outside she resisted and we had to force her into handcuffs.  While doing this she complained we were being too rough with her and that she was pregnant and if her child died as a result of our "rough" handling she would have us charged with manslaughter.  Then her mother showed up from nowhere and started to demand we release her offspring.  She was pulling at my arm and tried to get in the way of the arrest so I held her back while my trainer took the suspect back to the security office.  Oh yeah, and the suspect complained the handcuffs were too tight.

Number Four

I was working as the night clerk for a hotel in a downtown area of my city where there were a lot of bars and night clubs. After they closed it was common for intoxicated persons to come and want entry into the hotel to use the washroom or have me call them a cab. However, the building was off limits to anyone except guests at night so I had to turn them away. One gentleman didn't like this and decided to pound on the front doors and scream various obscenities at me including "Penis face" and "Fag". I personally like the "Penis face" one; A for originality!

Number Five

Working at the same hotel I heard a commotion outside and went out to check.  There was a very intoxicated blonde woman walking down the street with her friends.  When she saw that I was looking at them she retaliated against my unprovoked interest by referring to me as "Beef jerky".  To be honest, I don't know what that means but I presume I'm just out of touch with today's modern insults.

Number Six

Again, at the same hotel, I was once again working the night shift.  Some young men came by and wanted to go up to visit their friends who were staying in the hotel.  At first I was going to allow them to but, as they were headed upstairs, I heard one of them state that he was going to trash the hotel so I told them they had to leave.  One of the duo was fairly polite and was trying to negotiate with me but the other became loud and profane and started yelling such things as, "It must be nice to have so much power, eh?" and "I bet you think you can kick my ass, huh?"  After I told him that they had about 5 seconds to leave the building or they'd be leaving in the back of a police cruiser his friend subdued Mr. Angry by hitting him in the head with a bag of potato chips and telling him to be quiet, however before he left he threw one final "Fag!" at me.

Number Seven

Working at a hotel (a different one this time) I had one guest try to check in and receive the discounted government rate.  However, his wife had booked the room and she was the government employee, not him, so I told him that she'd have to come in and present government ID before I could check him in.  She was only outside unloading the vehicle so this would only take a moment or so.  He became very angry and demanded to be checked in right away and then shredded the registration card with his pen and yelled something like, "Here!  I'll sign it!"

Here ends my random sampling.