Princess does give robes in each cabin. We sailed Princess twice and even though they gave us robes, I thought Princess was far inferior to Royal Caribbean. Royal Caribbean's cabins are much larger, and the food, plus entertainment on Royal Caribbean was far better than Princess. That said, I consider the robes a non-issue.
We're looking forward to cruising from Baltimore on the Grandeur on June 23, and I hope that Royal Caribbean will met and exceed our expectations, as they have in the past.