As Tomous has said, a rapist (in fact most offenders) will struggle to get a job after leaving prison. Most jobs will check your criminal background and will refuse to employ people who have criminal convictions. When it comes to job opportunities Ched Evans is not being picked on any more than any other offender.
Ched Evans has also not fulfilled his sentence yet. He served half of it in prison and is currently out on license. This imposes quite a few restrictions on what he is and isn't allowed to do. For instance, he is not able to join a foreign football team as he is not allowed to work abroad and this would have an impact on a British club that might want to play matches abroad. (
http://news.sky.com/story/1401597/rapis ... ing-abroad http://www.bbc.co.uk/news/uk-30699017 ).
As a convicted sex offender, there are a number of careers and jobs that he is barred from. He cannot teach or work with children, which would be an issue to any club as he would not be allowed near the youth side, the mascots etc etc.
So while he has not been banned from playing football, there are a lot of reasons why a club would not want to take him on and they would be perfectly legally and morally justified in refusing him employment. Fans are also well within their rights to demonstrate and complain if their club is thinking of signing somebody like Evans. Sponsors (and let's face it in football it is the money that talks!) are within their rights to pull out of paying money to a football club if they think it will harm their image.
I have said before that Evans shouldn't be banned from playing football, but I would not want him near my club and don't blame any club for not wanting to employ him. Having the right to be employed doesn't mean anybody has to employ you.