Basically, Uniswap's website frontend which is owned and run by a centralized entity in Boston has hard-coded some trading pair routes and it's causing price desync with other pairs which allows arbitrage bots to drain profits out of it. On one such bot (etherscan.io/address/0xfe7f0897239ce9cc6645d9323e6fe428591b821c) you can see almost 22k transactions in 10 days with over 352 ether collected.
Guys, this very well may be the reason why UNI is dumping so much in price. Keep in mind that this kind of arbitrage would not be possible if the Uniswap frontend was coded correctly, we really need a new Uniswap frontend done in a way similar to Metamask