I kind of think this is a problem 🤔. I think I encountered this also when purchasing a channel from blocktank. Incoming payments were a lot more expensive than the default fees from robosats. It took me a while to figure out why I can't receive the sats I purchased. 

Yes, it's called fee siphoning and I believe wallets already do that. It's part of their business model. CashApp and ACINQ (the company behind Phoenix) are examples.

Isn't this what is called fee siphoning attack? Also what would prevent something similar happening in the hypothetical future where merchanta use lightning? A merchant sets a node with high fee between his node and you and charges high fees from his customers?

security

Stealing Sats from the Lightning Network Custodial Services (2022)

Isn't this what is called fee siphoning attack? Also what would prevent something similar happening in the hypothetical future where merchanta use lightning? A merchant sets a node with high fee between his node and you and charges high fees from his customers? 