Cost is about 15€/month for a compliant off-the-shelf solution.
I understand that there can be some tolerance in the beginning, but at some point, you can't look elsewhere, especially when the log is actually needed in an investigation.
Chances are that you'll buy this software as the bar owner. You are promised that everything is compliant. Years later it turns out that the software itself collected and sold PII and you're liable for the damage or that the software simply wasn't compliant after all.
Picking out cheap and subplot software that needs to adhere to nebulous requirements is not easy for a layman.
a bar owner isn't a layman but a business owner, and in fact one who already has to navigate regulations around media in particular. For example if you don't get a TV license if you put a TV in your bar and show say, soccer games, you're in hot water too and everyone knows this.
If you act as a service provider in a business I honestly don't know why people would be surprised that there's some caveats.
But my point is that the €15/month solution is not actually €15/month because of the reasons I outlined.
Quick perusal indicates Cour d'assises is the only court with a jury analog, and it only deals with matters where the penalty would result in a >10 year sentence if I'm reading it correctly.
On the other hand, plea deals are not a thing either, so if the state decides to press charges, you're definitely going to see a judge.
Across the pond, things work a bit differently, and the criminal justice systems are a bit lower friction for the authorities as I understand it. Not that I'm criticizing mind. The American System has not endeared itself to me as of late.
When it comes to MAC addresses, 1) there isn’t a central registry of addresses anyway so having the MAC address alone won’t help much in an investigation, 2) it can be set by the user so malicious users will fake their MAC address and 3) for privacy reasons most devices nowadays will generate unique MAC addresses for each network.
The IMEI and advertising ids are the more pressing ones though. Never underestimate the deanonymyzing power of someone else's UUID you aren't even aware you have.