Sure it's no big issue to be changed, but then what should the limit be? 15? 20? When does it stop?
Ten seemed like a reasonable number to have, in that this issue hasn't come up before.
I ran into this issue when tryin to sell some stuff awhile back, had like 15 or so items and had to post 2 pages. 15 would be a good number to go with, IMO of course.