I'll respond to your personal message.

There is no magic to getting free KMS. Some locations are not corporate owned and as franchises they limit their offering of free KMS.

0.25/KM is not bad for Sudbury. It could go as high as 0.60 as you've pointed out (crazy though, what's up with that !!), but the usual is around 0.49.

The renting location is getting your money though, so after all your bookings are made, I would call the renting location and ask them if they could quote you a better rate than you already have. It can't hurt. Especially if they know that you have done this trip before and will likely do it again in the future. Otherwise, stick with your own bookings.