Hey Steven,
Don't let this discourage you. I just went thru the same thing launching my site ravndrop.
I just assumed I would be able to use the default payment options with one of the main, easy to use processors..boy was I wrong. It turns out that all the main, known, easy to use processors use "aggregated" merchant accounts. This basically means that they lump you and thousands of other vendors into one merchant account which receives payments during the day. At the end of the day, this merchant account is batched out to all the respective personal bank accounts.
The reason that these aggregated processors won't do business with you is because of risk. It has nothing to do with the fact that vaping is looked down upon, or legislation, or big tobacco or anything. Its purely financial risk. They have data that shows vape shops for whatever reason have higher incidence of chargeback and credit card fraud, and thus the underlying bank won't allow those types of accounts to be lumped into the aggregated merchant account.
The solution is unfortuneatly pretty confusing and time consuming, but its not too bad in the end. You need to work with a payment processor who will underwrite a merchant account for you personally. You may need to pay slightly higher fees, or prove good credit in order to be approved, but it is possible.
Good luck, hope I shined some light into this murky financial industry.
-- Brian, Founder Ravndrop