Here is another thought on beach towels to take ashore. Go to the pool area and pick up a couple of the pool towels. They are similar in size and weight to the beach towels left your in your cabin. Two main differences-- they don't say "Celebrity" and you are not charged $28 if someone steals one. When you return to the ship, take the towels back to the pool area and toss them in the hamper at the pool.
The pool towels are very nice but I don't think they would be taken as quickly as the towel left in your room. The pool towels have all been laundered many times and don't shout out "new."
Celebrity does not put their name on anything they feel would make a good "free" souveneir. Just imaginge, they would have a trailer truck at dockside each cruise filled with new linens if they put "Celebrity" on the towels. This would replace the trailer truck full of towels leaving the ship in passenger luggage.
I would not dream of leaving a towel at the beach or being more careless with it just because it doesn't belong to me. But, I would be less irritated if someone stole a towel that belonged to the cruise line.
Les