Two things I'd guess at.
1: the money from the sim bundle probably wouldn't have bought many lunches. I don't know IG's split or whether Headup were the only publisher or not but assuming they weren't and the low amount of sales the bundle pulled in, I can't see that bringing much cash in. I guess the BTA split would be even smaller still so...?
2: It's Greenlight. If it makes a noise, hit it with a stick and see if anyone notices.
I suspect that even giving it away for free won't tip them over the threshold but who knows? Given the Steam audience, I don't think they'd have a hope in hell of being passed over most of the time so it all helps.