Paying to get on exchanges is annoying but I feel the dev should bite the bullet and do it. Sell enough onions on nova to get the necessary BTC, even if that crashes the price for some weeks.
I don't think the terms of listing on exchanges is only paying now, there are some other terms that is not revealed to the public maybe it is included in NDA agreement.
I think the dev team has their own plan and rationale regarding getting to a new exchange. It's not just about paying some BtCs. Some exchanges have their rules. We may need to wait until the airdrop finishes in order to get to some big exchanges. Let's hold and be patient.