State your set up size, not travel size. There may be a tree at the back or side on shorter sites. That does not mean they are less desirable, au contraire, mon cherie!
The previous poster suggested dishonesty to get a larger site, in the rationale that all sites are equal in price or availability.
While we do not differentiate site size in our rate structure, it is common in the industry to price preffered larger sites differently. For many camps the best, biggest costs more, for many others, the best biggest is reserved by the first come, first served.
Dishonesty serves noone well.