Wrong information, time and money wasted!

I am French and was in Cairns in January 2015. I called the jetstar booking service, bought a one way cairns-bali and the seller positively confirmed that jetstar would let me board without an Indonesian visa. When I arrived at the airport they had a sign over the counter saying " no boarding to Bali without return ticket withing one month" ! And they didn't care I was confirmed the opposite when I bought the ticket by phone. Ok so I bought a Jakarta Singapore that I finally never used.... And when I arrived in Bali I could not use their special extension of one more month at the airport, since at that times I thought I would leave the country after one month to use this jakarta- spore ticket that I was forced to buy. (I finally flew from Bali to Bangkok). How comes this company, when they surely must know that Indonesia offers either one month free or two months for a small fee when you arrive in Bali airport without a visa, oblige its customers to buy another ticket to be able to board and therefore force them either to lose the money of this ticket or the opportunity to stay 2 month in Bali instead of 1.

International
Australia-Cairns
Indonesia-Denpasar (Bali)