Most couples find that filing jointly makes the most financial sense, but in some circumstances, filing separately will leave you with a smaller total tax bill. (fool.com)
However, I believe you would normally deduct the amount of total tax paid from your state or local tax return. (money.stackexchange.com)
That leaves the ETF issuer with shares bought at or above today's market price, thus reducing the fund company's total tax burden even further. (etf.com)