Depending on the jurisdiction, price tags also have to be correct as well.
In certain areas, the consumer laws are such that the lowest of the register price and the displayed price must be used, and in other even friendlier jurisdictions, a discount of $10 has to be applied to the shelf price if the shelf price is lower than the register price (including giving away the item for free if the item is worth less than $10).
In those jurisdictions, ensuring that the price is correctly synchronized between displays and the registers is significantly more important than in jurisdictions with weaker consumer laws.
Where I'm from, many items have to have an easily comparable and visible price per kg (or e.g. l). Works so well (for the consumer) when you are looking at a selection of a specific product category.
Handling all this data and keeping it up to date is much easier with digitised and synchronised displays.
I'm not convinced that the synchronisation is assured. While paper labels maybe subject to lack of staff or process discipline, electronic labels are going to suffer from power/battery issues, connection issues to the database, physical product ending up on the wrong shelf, etc. It'd be interesting to see independent reports on error rates between the two methods. ( Our biggest issue is double-scanning of product at the cash register.)
In certain areas, the consumer laws are such that the lowest of the register price and the displayed price must be used, and in other even friendlier jurisdictions, a discount of $10 has to be applied to the shelf price if the shelf price is lower than the register price (including giving away the item for free if the item is worth less than $10).
In those jurisdictions, ensuring that the price is correctly synchronized between displays and the registers is significantly more important than in jurisdictions with weaker consumer laws.