Bittrex Delistings

Bittrex has announced that they will now be removing Monero, Zcash, Dash, and Grin. All of these coins feature privacy protections and I'm guessing this is why.

Bittrex also recently delisted XRP. So, I'm wondering if they are thinking that the privacy coins are next on the SEC's list of targets and this is their pre-emptive action to avoid legal trouble themselves?

Monero dropped 10% on this news. So, I bought some. This is a coin that will always have a purpose IMO.

Anyone have any clues into the why of this?