I have no doubt the church would ban anyone with drinking problem or that committing adultery. Softball players represent the church and, thus, should be good examples for the congregation.
Let me clear this up scripturally. As a Southern Baptist Pastor...this church has the potential (and I admit I do not know the facts) to be both right and wrong.
First...I agree with the first poster that it is unlikely they will ban all unrepentant sinners...but it is also unlikely they will know which guy out there is engaged in adultery or serial internet porn. The issue the woman is engaged in is a little more open. However...scripturally...this all rests on whether or not she confesses to be a Christian.
1Corinthians 5:11 - "But now I write to you not to associate with anyone named a brother, who is a fornicator, or covetous person, or an idolater, or abusive person, or a drunkard, or a swindler--not even to eat with such a person.(12)For what have I to do with judging those also who are outside? Do you not judge those who are inside? (13)But those who are outside God will judge. Therefore "put away from yourselves the evil person."
The 5th chapter of 1st Corinthians is a great lesson for Christians living in sin. So...if this person (any person) is Christian...this Church is doing the right thing...even if they don't apply the lesson without prejudice.
Now...according to the SAME passage and the examples of Jesus...if this person is a "christian" (note the small "c"...meaning they are one of these I believe in god types...the earth is my mother and Jesus was a great fellow and I believe in him so I am a christian (so they really aren't)...then the Church is doing the absolutely WRONG thing according to the Scriptures.
"But those who are outside God will judge." We are not to judge those outside the Church. Period. Their problem is not their drug issue or homosexuality....but the fact they are without Christ. That is the Gospel.
Jesus ATE with sinners. Jesus associated...spent time with....hang around....SINNERS. The Church is certainly in the wrong if this person is just a random person who does not know better and they are doing this.
Jesus would have never done this. Paul would have never done this. Paul only enacted Church Discipline on those WITHIN the church. He NEVER enacted Church Discipline on those OUTSIDE the church because he was afraid of church people catching the cooties.
The self-righteousness of some church people astounds me. They want to be "fishers of men"...but they expect the fish to jump in the boat all filleted...gutted...and scaled...smelling like roses.
The issue the woman is engaged in is a little more open.
But would not have been had the organizers of the league not felt the need to ask her about her private life. Something that they don't seem to do for the other transgressions you mentioned.
I admit that I am not a Baptist. I was raised in another religion and currently practice a third. And I admit that I am troubled by any church or pastor who practice double standards where sin is concerned, and whose solution to sin is to ban the sinner from their presence. As you yourself pointed out, Jesus Christ lived with and sought out the sinners in order to bring redemption to them. He did not ban them from His presence. It would seem to me that the Christian thing to do would be to accept this person into the team and to try and bring about a change to her behavior through fellowship and example rather than just casting her out.
That is different than letting an unrepentant represent Him. Those representing a church have an obligation to be of a higher moral standard, even if they are playing softball.
Jesus rebuked unrepentant sinners and told His apostles not to cast their pearls before sinners.
The body of Christ as a whole is doing a lousy job of rebuking sin and that is the primary reason for the rapid moral decline of our nation.