Can you really imagine how this would work IRL?
"-Here you go sir, that'll be $32 please."
"-OK, I'm paying it Bitcoins... Oh, you don't have an open channel, I'm going to create one... Mmh, but how much to I put in? Let's say $100, I'll probably buy here again next week. But will that be enough? What if my total is just above that next time? I'll have to pay the fee twice. I guess I'll just make sure not to go over $100."
"-We also accept cash, Visa and MasterCard sir."
Again, maybe it can work, it just feels so "theoretical" so far, I haven't seen anybody paint a convincing picture of a what a "Bitcoin as Visa replacement" world would look like concretely.