Known problem (since Alpha 0.31!). Probably it's the same as the free rush-buy from the shipyard Quick Build pop-up window.
You can abuse it as much as you like if it helps you to test other things (e.g. ship combats in Beta 4 
) This is Beta with the debug console, so you could just pop open the console window and type in a million bc for yourself to achieve the same effect. For Beta testing, it's all good.
