well I am no expert, but even today off-chain takes a lot of micro transactions...
many inputs can be collected and sent as 1 payment instead of thousands...
you only truly need on-chain to securely move big amounts of money...
think of it as debit account, shop gift card without expiry date or a check book, you put $1000 worth to your local shopping account and don't pay any fees every time you make a purchase, shops will love this too, because they would only need to cover BTC --> fiat from time to time, min deposit should apply, because this wouldn't work if users spam shop with small deposit trash transactions...
all the benefits of crypto still apply:
no counting the change, no password typing for a credit card, and no need to carry wallet whatsoever, free pockets (which leads to pants keeping good looks for longer time) and so on
the only problem I see is recognition... do you get an ID card or some electronic no contact device to prove you have debit account...