The pricing model is made so that if your map gets any kind of traction on a blog or news website you're bound to be looking at a $500 - 1,000 bill.
Maps are charged per view. A view is 4 tiles on the screen. So most likely as soon as a user loads it and pans they've already used 2 views.
Not the easiest model to relay to clients since it's hard to estimate the amount of map views they will actually use, since one viewer could pan around a lot of the map and use 50. Someone else may not pan at all and use 1.
Other than PAYG model there is only one other, Commercial. Which is $500/month. Instantly pricing out most small agencies. There did used to be about 3 levels all with different map view quotas, which was better for scaling up your production pipeline.