We do end up collecting devices. Hell I have to round up consoles because I've caught both of my kids up in the middle of the night sneaking into the living room to binge on shit at 3am on a school night. It's exhausting. Some nights you just forget because we are human the entire concept of having to go draconian on electronics is stupid in the first place.
But just wait. You'll understand the addiction and the lengths kids will go to get their fix.
I've been dealing with this lately with my girlfriend's kids, and I'm somewhat fortunate that they haven't figured things out as much as yours. I use a Ubiquiti setup that is able to monitor the data for all devices connected to my network, which includes statistics on recorded down to a 5-minute interval. If you're using data on my network when you're not supposed to, I will see it, and I have had to deal with it. As an aside, the part that really grinds my gears is when I confront them over it, and they lie to me. I'd like to switch to using all iDevices mostly due to Apple's Screen Time being a fairly effective tool in deterring improper phone use. Although, going back to Ubiquiti, even though they're kind of trying to push more into the consumer space rather than just enterprise, they do lack features that would be helpful. For example, there's no way to set time limits on WiFi for specific devices. The only way to do this is to setup a separate WiFi network for those devices and establish a time limit on that wireless network.
As for device collection, that's what my girlfriend does and I'm not a fan of it. The big reason is that
I want to give them the opportunity to fail. I want to be able to say "I'm giving you the responsibility to not use your device when you're not supposed to, and I hope you don't break my trust." To be honest, I'm betting that they will do it, but that's fine. They'll get punished (likely lose the device and other devices for a period of time), and we'll hope that they learn their lesson. If they don't, the punishment just gets more severe.
I do think that George Carlin skit was somewhat onto the right track; however, I don't think the issue is purely structure, but rather, the lack of a reason to grow up. (It's worth noting that excessive structure can cause that.) I don't think I'm saying anything new or surprising, but children tend to lack the life experience that helps outline why we do what we do. I mean... this isn't the Little House on the Prairie days; the expectations on childhood have changed drastically over the last 50 years. One thing that I try to do is be a bit more forward in regard to the adult reasoning for things.
As a kid, I was the one that would ask "why?" a lot, but it wasn't to be a pain... I simply wanted an understanding. (I was that kid that would take things apart to figure out how they worked, so that's not a huge surprise.) Although, in regard to kids, I find it's better to work with the tangible rather than the intangible. For example, I've been dealing with wastefulness lately, and what I want to do is start putting the concept of a dollar amount to actual things. For example, if a kid tries to push off finishing an $8 Chinese takeout and would rather throw it away, I'd say "Alright, there's half of that left, so you owe me $4 if you want to throw that away." I think it's better to put a dollar amount, which matters more to kids since they don't often have a lot of money, rather than intangible things like "Do you know how much we had to work for that food?" It's pretty obvious that they have no concept of the value of money when one of them suggested that they probably earned $5-6 for putting the dishes away. I had trouble containing my laughter when I heard that. I think I just said something like, "$5-6 for 3 minutes of work? I'm quitting my job today!"