No not at all .. first off its only the last 4 digits they can see. And how on earth would they even figure out ..
our payment systems aren't linked. we have no way of knowing what you buy (except our product) and nether does blizzard. the only people who can see that you bought both is your bank (or credit card company) and you (and the government if they can subpena your personal financials but thats besides the point.)