I do not think, if your customers number less than hundreds of thousands, that getting the custom of folks for whom $9 is a lot of money is a worthwhile use of your time. Devs consistently overestimate the impact on their marketing/etc of having cheapskates use them, and underestimate the real operational costs. (These customers are disproportionately pathological; they contact support rudely, with inane questions, at a rate orders of magnitude higher than good customers.)