Near as I can tell, Li-Ion batteries do NOT last longest when topped up frequently. They will last 300~500 complete charge cycles. While it's claimed that they don't have a memory, there's zero harm in running the battery low. If you trust the claims (my experience is in IT and mechanics, not batteries/chemical engineering), then topping up frequently also presents zero harm.
You can harm the batteries most by not allowing them to charge and discharge (leave the reader tethered all the time), by allowing them to deep discharge (go Completely dead, not just "shutdown" dead, but days of attempted use past that), and by using them in Extremely hot and cold environments.
Regardless, not one single post in this thread speaks of Anything that would... let me quote Poppaea here:
Not sure how using a Consumable item would equate to that in any case. Do we all hurt our cars/motorcycles/scooters/trains/airplanes/buses/etc... when they need their batteries replaced? It would be safe to say that no matter how an individual chooses to use their device, they Should all last the same number of complete charge cycles based on the information that's available to the average consumer.