none of the romance languages would use the verb root "avoir/tener/etc" to imply an imperative

Inselpeter y yo tenemos qué desavenirnos. The use of habere/tenere and their modern descendants as markers of necessity are quite common in Vulgar Latin and the Romance languages as see our posts above (or below for Threadnodists). Without digging too deeply, English is the only non-Romance language that I can think of wherein this is the case.