I've always been fond of oddball colors myself so I'm sure your boy is very pretty.
The purpose of breed clubs and a breed standard is to set up an ideal for the breed (an idea of how it should be) and to work towards making sure you don't lose that breed type.
You can read the breed standard here
http://www.akc.org/breeds/boston_terrier/index.cfm
There are lots of ways for a dog to not 'measure up' to the breed standard including color which is pretty easy to spot.
The problem is the people who are not breeding to meet the standard, including ones who are breeding for 'rare' colors very often pass along other problems while trying for the color they want. Any time you breed for any one single attribute, instead of the general look of the breed, you can run into trouble with other portions of the dog. For example you breed two pretty liver or red dogs to get colored pups and you 'forgive' the knee problem, the spine issue, the breathing problem, a hip issue, or that the dogs are way too big in order to keep the pretty color going. As the dark colors are the norm in the breed the 'off' colors have a smaller gene pool to begin with which can lead to more problems.
Your dog may be beautiful to you, smart, a wonderful companion etc. but still not meet breed standard and thus would not be considered suitable for reproducing because of that. The entire goal of purebred dog breeding is to get pups that are predictable and like the parents.
No one person writes a breed standard - its a group of people who love the breed and want to preserve it that do that. People in the dog clubs usually are ones who also feel that way. So your dog wouldn't fit in with those ideals. He's a dog of a 'different color' but personlly I'd rather see that than a Boston with a poor temperament or spinal problems etc. Its just the color is easier to notice right away.
Now with your dog there are lots of activities you can do to show him off if you want to - you can train him and show in the obedience ring, the agility ring, the rally ring just not in the breed ring which is for dogs that are breeding potential or hopeful breeding potential.
You may find the performance people lots friendlier to deal with too.
Hope this helps you!
Dog Expert:Rescue, Train,Breed,Care
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics