Flight Cents?

I just received and invitation for a pilot program called Flight Cents.
They will round up a purchase up to the nearest dollar and award a mile for every cent (u to $500).

That means that I can load Amazon with $1.01 and they will give me 100 miles for that, as far as I understand this correctly? It will be possible to get up to 50k miles per month. The program will last for 6 months, so up to 300k.