I treat the spirit of these licenses as: "if you have reasonable expectation of making money from your use of it, please buy a license. Otherwise, we appreciate the mindshare."
Practically speaking, the license is probably much closer to "if you are making prodigious amounts of money, and you are using our software, then you had better buy a license to avoid a legal situation."
And if I were making prodigious amounts of money I'd be happy to go back and pay JetBrains the $274.8 a year that RubyMine costs per person for a company license. Aside being the decent thing to do, I'd like to contribute to JetBrains so they continue updating a tool that helped me build my company.
So any VC funded startup should use for free in your opinion?