I see what you are saying but your logic is a little flawed. Say 2 men marry. Man 1 pays $10,000 per year in taxes and Man 2 pays $10,000 per year as well. If they marry, they will not pay $20,000 in taxes...maybe they will only pay $18,000. So the government loses $2,000 here.
Trust me, the government will make up that difference somewhere by raising taxes.
Again, I know its not very popular to look at it from a purely financial standpoint...but it's necessary in the type of country we live in.
I do not trust your math on this issue.
Say each earns $40000 per year.
Single person pays $6558 in taxes.
Married file seperately $6558 in taxes.
Married file joint $13115, a grand total difference of $1 in favor of the taxpayer
If each person earns $80000 per year each.
Single person pays $16732in taxes.
Married file seperately $17102 in taxes.
Married file joint $34,204 a grand total difference of $740 in favor of the government