lo/loi

["Mr Ekted" <mr_ekted@hotmail.com>]

I've been working through the lojban lessons, and I have a question about translating the following sentence:

"No more than 15% of Buddhists eat meat."

The answer page says it's:

"su'e pipamu loi budjo cu citka lo rectu"

But by my understanding (admittedly new) it seems almost overkill to use loi here rather than lo. "15% of Buddhists" compared to "15% of the mass of all Buddhists"? It seems like there is no distinction of meaning, as there is with le/lo. I can understand being "picky" with meaning to avoid ambiguity, but this case seems to be different. Is there a subtle difference meaning that I am not understanding?

Also what about this:

"su'e pipamu ro budjo cu citka lo rectu"