No, it would ward off a lot of legitimate players, Chinese sellers are often involved in the credit card fraud business and trade stolen numbers which they could use for registering accounts, lots of people don’t have cards, lots of parents will refuse, it creates a risk of hackers stealing your number (IMC is known for bugs), and best of all, my card lets me generate throwaway numbers for temporary use so I could make a bunch of extra accounts if I wanted. Even if IMC posted a test transaction to verify that the card is real, I could mass produce and sell accounts.
On the contrary, making them pay for stuff and then banning them so they have to pay again is a good way to deal with them. The developers will make a profit off the bots, they’ll have a financial incentive to ban them frequently so they’ll have to pay again, and botting activity will be limited to the relentless ones who are hard to get rid of anyway.