I think the culling issue is important to discuss but this really isn't the thread for it... if you want to argue ethics then maybe you should start a new thread and do it there... back to the real issue here:
I have alot to say, I'm sorry in advance for the long post...
I am not a breeder and I never will be due to the time and money it takes to really be sucessfull at it and do it right. My final thought on this matter is this: 5green if you really want to breed for the RIGHT reasons, then we do not have the right to stop you, but can only wish you the best and offer up our advice. But PLEASE be warned that it is NOT somthing to do "just for fun" and definitely not somthing that will make you money. Clearly you care about your fish, other wise you would not be using this forum, but when you breed you put your fishes life in danger and that is a huge risk to take, its not about how much research you've done, things can still go very wrong very quickly. We know you care about bettas as much as we all do and I'm just asking you to really way out the benefits ( if any) vs. the risks.
Think about it this way:
You could breed your bettas, spend upwards of $100 on equipment, jars, food etc. In the end you may have 100's of bettas which you either have to cull or find homes for. And if you cant find homes for them then you have to spend the money on tanks for all of them, because we all know you cannot keep your fry in jars for their entire lives. Or you may end up with no bettas becuase your pair injured eachother to the point of death and you had no fry.
With the money you would spend on breeding equipment you could buy 3 new awesome five gallon tanks with live plants and nice filters and heaters and buy three new bettas! and you would be giving them a great new home and saving them from the terrible conditions at petstores, instead of contributing to the huge population of misstreated bettas already out there.
Again, sorry about the long post