Legal Marijuana Use

We have all heard about it: marijuana used strictly for medical purposes only.
Currently we have 14 states that have in some form or another legalized marijuana.

Interestingly, since the beginning of time marijuana has had many, many uses. The plant itself is used for fabric (hemp), rope, food, and even incense. It has also been viewed as a useful plant for many different things and only in the recent decade has it been considered a potential danger to people.
Marijuana has helpful for many things over time and was not ever used in terms of smoking until more recently.

Which brings me to the recent topic seen on msn.com: Wal-Mart employee fired for marijuana use. The 29 year-old fellow, a 5 year native to this particular Wal-mart suffers from an inoperable brain tumor and sinus cancer. Making just $27,000 he supports his two children on that income. After multiple attempts at routine pain medication this man was not responding well to it's typical pain relief. His physician used his last resort: prescribed him regular marijuana use. The fellow always carried his medical card stating he had a prescription for marijuana use, however he was only to use it at home and away from work.

This young man claims he never went to work high and was always careful when using and never ever smoked while on the job. However, after looking at Wal-Mart policies, the manager of the store opted for a random drug screen on him and fired him on the spot once finding the results.
The kicker is: can a medically prescribed drug prevent you from getting a job? It can in most states. If employers believe that you are potentially going to violate a policy that states "all employees who are a potential safety hazard or may cause negligence to customers must not remain employed" (I paraphrased) they may fire you.

Sadly enough, this man has spoked with many different lawyers and despite their own personal furry for his tragic situation they are unwilling to take on his case because of federal law. Federal law is held above state law. So this leaves this particular man in a sad predicament: he can't work because he has been given medical marijuana, but now he can't pay his bills. What do you do in a situation like this?? Live in constant pain while working or lose everything to be pain free?
I hope I'm never in this situation.