I often wondered about the drying out. When I first tried starters, I constantly struggled with the drying.That is not best for storage in the fridge. The tulip jar with the wood lid will pop off if there is pressure. It has a seal too so the starter does not dry out.
I’ve always seen the admonition that, as a starter ferments, gases will build up in a sealed jar and risk exploding the vessel. This makes sense, as other fermentation processes (beer making, for example) use bottles with release valves in the earliest stages.I wonder where the idea of not sealing starter comes from? I have always sealed the starter in the fridge. It will keep for a couple of months that way.
I’m with @BigBlueHen53, $30 for a pair of jars is steep. If there’s a workable alternative using something I already have on hand, I would prefer that.
Have you ever had a jar lid pop, either in the fridge or out?