Agree!
I think it HAS to be. I think it has to be frustrating for men looking for women as well who have men respond.
If someone it's straight but doesn't specify what sex they are looking for, ask away, but if it's someone who is bisexual, when they state they are looking for one sex, people should respect that. Mostly, it shows an unwillingness to pay attention to the obvious, let alone details, which is what I assume most are wanting in a partner. If you're not going to listen to what someone says, why would they want to play?
A much better response would be NOT to reply to the ad but send them a message or friend request to possibly make them aware of your profile. A friendly hello may work wonders.