We're Amazon Prime subscribers so the only time I worry about minimum orders is for their free same-day delivery, which has a $35 minimum order.
The last time I used the free same-day delivery, I needed to replace a RevoShift shifter and needed a cable cutter. The total wasn't quite $35 so I added a bag of super-caffeinated coffee.
My usual top-up orders are things like cat food (Blue Buffalo or Taste of the Wild), good coffee, household stuff that's not easy to find locally.
I'd add beer to top up my free same-day deliveries if Amazon offered it. My local stores don't have a good selection of traditional ales.
My only complaint about Amazon's new free same-day delivery is they don't have an efficient filter to quickly locate eligible items. Orders must be placed before noon, and I usually place them the night before or by 6 a.m, which usually ensures deliveries by early afternoon. But it's a PITA to find eligible items without a proper filter.