Well, I talked with a guy at NAMA about having vending machines accepting and dispensing halves as needed, and he told me that the coin mechanisms can't accept them due to size and some other issues I forget (As one member here stated) and I asked if they could be modified, and he said "How many vending machines are we talking here?" and I said "One to three or so" (That small sentence, "One "to" three" was almost like I was counting, but I was not ) and anyway, he said, "I can't do anything for you. If you were talking 3,000 machines THEN, I would be willing to do something for it, but not just three" But hey, if my business kicks off good enough, and I extend my business into real estate, and am making tens of thousands of dollars a year, I will try to get the vending industry's attention on half dollar acceptance and dispensing. I know it won't be easy, but it could happen if I do it right. Maybe if I start circulating halves through my shop, and they start showing up in a few more businesses, maybe then the vending industry will see need to update their machines for halves and $2 bills. But anyway, thats about it...
No commercially made vending machine coin acceptor will take a coin larger than 29mm diameter. The half is 30.6 mm diameter. Do the math. However, as I told you before, you can buy your own mechanism and have a machinist modify it on an individual basis for your own needs. You'll need an industrial designer to make the drawings first. The first one should run about $3-4000. then maybe $1000 each after that. These people don't work cheap.
Until someone can convince several corporations like Wall Mart to start using Halves and Dollar coins nothing is changing with either. The majority of people don't go to the bank to get coins stores do.
I'm just grateful the machines take new dollar coins! I just don't know why they keep striking halves if nobody is going to use them. I guess it's still a money maker for the Mint.
Current half dollars are an anachronism. They are minted for bureaucratic / political reasons only. Nonetheless, I want to conserve examples of them. Someday, they might be fascinating to those who come after us.