Yes, many (most?) of the dealership chargers are ChargePoint units that are either pay per use, or you need to ask for a card from the dealer to activate the station. However, the ChargePoint model is that the site host really "owns" the charger and is responsible for upkeep, keeping it accessible, etc. If there is a problem (either with the equipment itself or the electrical service), the host needs to call ChargePoint who will charge them for parts and service, so what I find happening is that after a few years, once the stations start to have issues, the dealers can't be bothered to call in ChargePoint, which will only cost them money, so they just let the station sit there broken.
Either that or some shady dealers will jack up the price of charging to such a high amount that nobody in their right mind would charge there (which is just fine by the dealer).
So when you find a dealer that is welcoming and helpful, it is a rare find. Usually those dealers will have an EV "champion" that welcomes EVs and sees treating EV owners with respect as strategic. But of course once the champion moves on to a different role/dealer, the new guy may or may not care as much.
Sorry if this comes across as being too cynical (especially in response to a positive report!), but I am hoping that dealers do figure this out and either wholeheartedly embrace offering charging, or just don't even bother at all and let the independent charging networks figure it out. I would certainly approach any dealership charging station on a trip with skepticism and make sure I had a backup plan. That said, for some of the places you traveled to, there may not have been many alternatives!