If they're adhering so "strongly" to the Bible, I wonder if they have actually read the Old Testament, as well. It's actually a scary thing to ask for a show of hands in a church as to how many people have not read the entire Bible, from Genesis to Revelation.
As for that passage, it's been said many a time that establishing theology on a single verse is, to be blunt, stupid. Besides, there's another instance where Paul gives his personal opinion on a matter, fully acknowledging that it is, in fact, his opinion, and not God's say on the matter, such as the issue of marriage.
All the moreso in this case, where he says "I do not allow a woman..." - it's obviously his personal opinion on the matter, undoubtably influenced by the culture and values of the time.