yeah, it's far from too expensive but at the same time as you probably know lightning payments use a source-onion-routed protocol and only timing info is visible to intermediate LN nodes, and many ecom operators are running tehir own LN infra like btcpayserver, i was using a VPS with this some time back, and have used several others as well, so it really is confidential between customer and vendor

when you say 0.03% is that by volume (sum of the sats value) or by individual transactions, because individual transactions are where the onchain fees come from, not the volume (leaving aside the cost of transactions with large number of component UTXOs)

if it's by volume then darthcoin the lightning maniac is right about that because he means transaction count

i dunno about any stats on the actual utilization of LN in terms of volume, i've got some beefs with the entire protocol over the matter of channel balance being opaque and this being the main cause of routing failures (especially combined with shitty routing nodes running on flaky ADSL connections in the middle of Australia and shit