I am a travel agent here in Michigan and I have never heard of such a thing, not sending you your docs because they cost too much to mail? That's nuts, your travel agent is making good money from your booking, they can truly afford the cost of shipping them to you. If i acted in this manner, I wouldn't be in business very long, and by the sounds of it, your TA wont be. It is true that you can get onboard without your docs, there are cruise staff at the ports (where you drop off your bags) with a list of everyone that is on the sailing, they have many extra luggage tags for you to fill out and attach to your bags, just have your proper I.D. with you and you wont have a problem. But in any case, do whatever you can to get your docs from your TA to assure no delays at the ship.