Clint, sorry, but I do not consider a semp offset to be a cutting. It is a complete, independent plant and has been designed by nature to be that way. Where semps are concerned, I consider a cutting to be a divided rosette, such as one cut in half or quarters. These will root and regenerate as well, but few people actually do that to propagate (or even know that will work for semps). Obviously, we have a terminology difference here, but I am not accustomed to hearing people label semp offsets as cuttings. Perhaps this is cultural or geographic difference at work here.
I checked the NH website and they indicated there that they would ship rooted plants where possible. I know that when I trade plants, there are frequently requests for plants or varieties for which I have to make the decision to either ship a small offset or to disappoint... In those cases, I always try to ship the plant, even if it is a single, small offset. My reasoning is that it is better to send something that somebody wants, than to disappoint. Especially with rare or new plants, I believe it is better to get them in the hands of multiple people - less chance of losing the variety that way. I do get your point about NH being a business, but most of the semp dealers I have come to know anything about began and continue to specialize in semps as a labor of love. They would send you bigger if available.
Another thing that could be at work here is that your order occurred (I believe) during the winter. Semps are not actively growing here during our sub-zero winters. I have noticed that plants vary greatly in size depending on time of year ordered.
NH is a DG Top 5 vendor and has a strong guarantee. If you are unhappy with your purchase, please contact them. They will make you happy. I have had personal experience with NH, SMG and Edelweiss Perennials and all were wonderful to deal with. There has been a wide variety in the size of what was received, even from the same vendor. I marked this up to the nature of the plant, how much was it was in demand, etc. In at least one case, I pleaded for a start of a variety that was listed as out of stock and they found a way to fulfill the request. They are all great people to deal with.