Yes, all ticket lotteries in general are free to apply, then your card gets charged only if you win that lottery.
In any case, I recommend to read well the terms of this year acomodation plan (once available), since is based on lottery, so there might be some differences compared to previous years ^-^
It's indeed interesting that there is lottery for the accomodation plan, probably because they saw that many fans wanted to apply for the plan, but couldn't because sold out in a short time.