Your explanation raises the follow-up question, which svantana already hinted at: Why don't construction cranes use hollow tubes instead of their typical truss structures?
Thus does the amount of material not matter as much in a crane.
For wind turbine towers the material cost can be >>50% of the installed cost.
* The margins for cranes are thin and steel is expensive.
* Thicker steel is harder to work with, increasing manufacturing cost.
* Each kg of dead weight may decrease the performance of your product, e.g. max. Live load. This is especially true for the jib.
* More weight at the top of the crane may necessitate a sturdier structure below, amplifying cost even more.
* More weight may require more ballast blocks, which are costly (especially transport)
* More weight means higher transport costs
* More weight means more wind area, which is the critical factor for high constructions.Interestingly, wind/storm loads are oftentimes the limiting factor for the configuration height of a crane.
This is because, when adding another tower segment, not only the total area increases but also the wind forces. The other loads stay roughly the same
This is the reason why bottom-slewing cranes, which are commonly used for small buildings, sometimes are built with solid walls. Top-slewing cranes, which are used for high buildings, always use a steel framework.