When I started to collect my watch strap collection, I was very worried about this: in some straps (most often factory ones), tubules were installed in the ears, and in the straps they were not on order. I even wanted to order in one shop at once 60 tubes for straps to be inserted into all future straps. Well, knowledgeable people dissuaded;)
Now I myself know that these tubes are not needed. For example, without them I can insert a strap between the arcs of the watch easier than with them. So I took them out even from the straps where they stood.