What makes you think $15 entitles you to a lifetime purchase let alone $2.99? What else in your life do you get to keep forever for that amount?
A pair of levi jeans: ~$50 of ~3 years; an iPhone ~$500 for ~3 years; a beer ~$5 for ~30 mins.
I bought a coffee in Starbucks yesterday. How dare they charge me for another today!
Most apps are priced at even less than a coffee. The profit on most apps is less than that on one tomato.
Yet, you feel entitled?