Unfortunately I don't remember what I bought with Lightning. Most of the things I buy online are over the Bitcoin network. I wanted to have an online piano subscription, to learn piano, but they only accepted creditcard payments. I ask if I could pay with Bitcoin and that was possible :-) They weren't were familiar with Bitcoin, but open to suggestions. Maybe to suggest using Phoenix wallet?

To help merchants accept Lightning payments, I think giving a demo workshop (free or paid) would be the best thing. As a merchant you get to experience it, not only see it. Besides that, a merchant for the first time sees a huge number of possibilities on the Lightning network to acquire new customers and have new business models.