How is working a casheir job stressful? Perhaps you should be doing some stress management research and figure out how to look at things in a less stressful way. I used to work cash at a Tim Horton's (Canadian coffee shop. If "Canadian" were a religion, Tim Horton's would be church). You know who's stressed out? A guy that just got his 3 kids dressed and ready for hocket at 6:30 in the morning and has to wait in line 25 minutes to get his caffein fix to get through his day and he might be late for his first kid's game. When that guy gets to the cash he tries his damnedest to offload that stress on the poor schmuck serving that coffee... Just be invinsible to the stress. When that asshole says "This is rediculous! I've been waiting 25 minutes for a coffee!" I'd just say "Wow... why'd you do that?" *grin*
Nothing makes me more relaxed and him more angry than that response.
As Farve in Supertroopers says "Ten deep breaths".