When you buy images you don't have to pay per month do you?
Why are fonts different?
Why are fonts different?
When I worked in the agency world, most of our clients' budgets were a bit too tight for rights-managed photography (RM is generally more expensive on top of being more restrictively licensed), but when we did, there was usually a fairly simple set of web form selects for publication type, duration of publication, audience size, etc.