Who says they didn't perform the kind of cost/benefit analysis you mention and estimated that it wasn't worth the effort? And if that was their estimation, despite our (NH denizens) collective annoyance, maybe they were right. Maybe providing free access made prospective paying customers less likely to pay for firehose access, or a slew of not-for-profit organisations requesting free firehose access citing emojitracker as a precedent. There's a myriad of hypotheticals and whomever made this decision is not necessarily irrational... it just depends on what constitutes their utility function.