I suspect that they (Escape) are happy to store the trailer as long as you want them to, but they would require that you pay for it first. Once you pay for it, it is yours and you are subject to a loss if anything happens to it. Thus, the need for insurance. This would be no different than having it sit in a storage lot over the winter months.
As a side note, I understand that if you get Escape to store your newly purchased trailer, they will not start the clock on your warranty until you actually pick it up (that is what they told us).
Dave W - 2013 Escape 19' and 2011 Toyota FJ Cruiser
"When you arrive at a fork in the road, take it." - Yogi Berra