Any particular reason why Arb bots are not buying BTC from finex and selling them on Bitstamp, Gdax and Gemini. Surely a spread of 5% plus that Finex had for quite some time would be worth it. I would think the arb bots would be bringing these markets closer together. What is Spoofy up to?

Bitfinex prices are not real USD but USDT, which is at this moment 2% over USD. That reduces 5% to 3% profit. Also Bitstamp doesn't do USDT. I think Gdax and Gemini neither.
That 3% is probably not worth arbitraging in a so volatile moment like this and Bitfinex adds too much third party risk over other exchanges (which also have some third party risk).
Lastly, you can only do that once if you have the funds already in both exchanges. After that, you need to transfer the funds, pay tx fee's, wait for only god knows how long until the exchange release the withdrawal and it gets enough confirmations on the receiving exchange.
So... in the end a theoretical 5% spread is not that much when all factors taken into consideration.
If you want to arbitrage you can find way better spreads on many alts.