The clerk is only telling you what the computer system is telling him. Do not make demands. Good manners are far more effective. When travelling in a group, only one person needs to stand in line to check in - not the whole family. If the front desk clerk bends over backward to give you excellent service, then by all means, show your appreciation with a gratuity.
Comment cards are great.
Ask for them at the desk or look in your room. Good comments reward good employees, and bad comments hasten the departure of bad employees so others don't have to deal with them.