If he doesn't like gay marriage, he doesn't have to get gay married. But contributing a significant amount of money to take away that option from someone else is wrong. And to believe it's his right to take that option away is wrong.

I have a same-sex partner, Brendan is willing to work and make a real effort to take away our recognition. To unmarry our children's parents. To eliminate our shared benefits, and impair the other 1148 rights conferred by marriage.

I am not happy that my money and time might go towards his salary and to further empower his views, so it's a logical decision for me to boycott his company. Many others feel similarly.

To be fair, at any point he could have said "My views have evolved, and I no longer think it is my right to deny others marriage.". He chose not to.