Bittrex will ask 7 BTC because they need to do some search if it's "legal" for them to add it. If they decide it isn't, you've just lost 7 BTC. That being said: Yobit is only 0.1, yes it's only Yobit but better than nothing.

And about the signature campaign: I also think it was useless (even though i have a signature) most of the buys (40-50k) happened in the first hour, people that wanted to buy, bought it, bounties are useles imo.