Why is it when I extrude a surface two directions with draft and capped ends does it automatically make it a solid???

Is this how it is suppose to function? There appears to not be the option (check box) of keeping it a surface or making the enclosed surface a solid.

It need it to stay an enclosed surface. I can work around it, yes (with more steps). But it seems like the option should be there. Am I missing something?

Also, it would be nice to be able to cap both ends of a single direction enclosed extruded surface as well as being able to choose which end you want to cap, start or end or both.