Does interesting work count as a perk? I don't really care about most of the perks that were listed (e.g. on-site dry-cleaning, professional mentoring or subsidized training) but the best way to keep me on is to make sure I don't get bored. If I have to ask more than a couple of times for more challenging work and don't get anything from my manager, I'm going to find it somewhere else.
A lot of the times ordinary office jobs consist of low morale repetitive tasks.. I agree with you, being engaged is a fundamental need of humanity.