I think we confuse compliments for common courtesy, like for instance if someone is working for me, it's should be common courtesy to say thank you or show care regardless of whether I'm paying you or not but it doesn't demand that as I see you on the job daily or weekly, I start giving you compliments, nah, I don't really think so.
So yea, employers can be more nice in gesture but to start demanding a compliment culture, I don't think that's good.
In the long term even.
It alo depends on what we call compliment like ulyou rightly said. An employer who is paying you for your service don't have much to do about compliments to an employee Pasay. In the first place you applied for the joke and agreed to the payment of salary and the facts that othe terms and conditions of the work you agreed to it. The employer can only be nice and friendly which is not a must to be. Because many employers see being nice to there employee as a link to be disrespectful to them.