Transgender bathroom confusion

I'm sorry but I'm a bit confused about this whole debate over which public restroom transgender people should use. First of all I can't imagine anyone willing standing in the usually long line to use the women's if they're actually men.  In fact I and many of my female friends have been known to use the men's if there's no line and we're desperate. This usually happens while traveling after long bus rides. The other question that comes to mind is who's going to be checking to see that no one breaks the rules.  According to a law passed recently in one state, a person must use the appropriate restroom based on the gender indicated on their birth certificate. Does this mean that we will all need to carry our birth certificates whenever we're in a situation where we might need to use a public restroom, and again, whose going to be checking? Of course this could possibly open up a new employment opportunity for retirees, something like Walmart greeters. Where can I apply to be a restroom gender checker?