The privilege of wearing a hunt’s buttons and/or distinctive collar is awarded at the discretion of the Master(s). It’s an honor, and also brings with it responsibility for the wearer. It means the Master(s) consider you a valued member of the hunt, based on your participation year 'round in supporting the hunt, and your abilities in the hunt field. Other riders should be able to look to you to solve little problems as they arise during a hunting day. You know the country, and the landowners, and help to keep them happy.
During the hunting day, those with colors are entitled to ride ‘up front’ in the field, with the caveat that when hounds are running, and a member with colors is Too Slow, ‘anyone’ in the field may pass them-safely- and the Real Member With Colors knows that. You do get some uppity folks who think otherwise- but they are wrong.
Let me just add that earning one’s colors is certainly an honor, and a nice touch- but it isn’t, or shouldn’t be, a ‘make or break’ for anyone. I’ve earned them with two hunts and have honorary colors from a beagle pack. But- you can have just as much fun hunting without colors as with, in my 38 years of experience!