The mint can charge a fee for deposits, internal transactions and withdrawals. The guardians (FediMint jargon for federation members) can also operate the LN gateways and earn tx fees from them.

LaserStack

Trust, network effects, and service performance/quality/interoperability seem to likely be the biggest factors which you already pulled out.

And how would a profit-seeking Fedimint group charge a fee for their service? You provide them a 100 sats and get the equivalent of 99 sats back in their own mint?

I'm the least clear on this. I suspect they could only reliably charge based on services they provide on top of the mint:

bitcoin

Can Fedimints Help Bitcoin Scale To The World?

k00b

Trust, network effects, and service performance/quality/interoperability seem to likely be the biggest factors which you already pulled out. 

> And how would a profit-seeking Fedimint group charge a fee for their service? You provide them a 100 sats and get the equivalent of 99 sats back in their own mint?

I'm the least clear on this. I suspect they could only reliably charge based on services they provide on top of the mint:

1. the exchange of Bitcoin for tokens and vice versa, but other people could compete with them on that
2. if they run contracts for people in the mint, they could charge a fee for that I suppose too