I work for a great company and I'm happy with my job. They also happen to censor my internet (very mildly, I should add). In fact, there are plenty of sectors where all viable positions would include internet blacklisting. And finally, plenty of people can't be so picky about their jobs to make litmus tests out of relatively minor factors like this.
Because at the end of the day, I need to earn money in order to live at a standard that I'm comfortable with.
Because regardless of privacy and rights, censoring porn at work is completely reasonable.