I worked in a restaurant whilst I was at college and each service we were told by the management what dishes we needed to push that day. We were even told to ask the diner if they were sure when they went against our suggestion. The reason for pushing a particular dish is either because it has a higher profit margin, or more likely, they have over ordered a particular item and want get rid of it

So take my advice, treat the server's recommendation with a metaphorical large pinch of salt