Oils (from the cedar) also keep the wrapper nice and happy.
Stella,
All the things you've already found out are true but there are two other reasons that don't get mentioned very often. Basically, cigar smokers tend to be very visual people. Using cedar or aluminum tubes prevents them from seeing any variation in color when opening a box. Otherwise cigar makers would have to reject too many cigars.
Cuban cigars are sorted by shade packed in a very specific manner. Darker cigars are always on the bottom row and the top level goes in increasing shades from left to right because that's how most people read. This is one of the simple ways cigar geeks can immediately spot counterfeits. No matter what people may think about Castro, Cuban people have far too much pride in their legacy to send out cigars improperly packed for presentation.
Tubed cigars are generally fine smokes, just not aesthetically pleasing enough to make the first cut.
Chaos,
I haven't ordered in a while.