There’s a few layers to this. You’re completely correct that you can use those boards for LoRa without LoRaWAN. I think what OP is looking for, though, is cheap LoRaWAN gateways that aren’t tied to The Things Network. Can’t use the SX1276 for that, since it can only time one receive frequency at a time.
There’s cheap gateways available that are hard-coded to talk to TTN, and there’s expensive gateways available that let you run a private WAN. There just doesn’t seem to be cheap gateways available to run a private WAN.
I have read rumors of alternate firmware to allow that hardware to work outside TTN but haven’t chased it down myself, so mine is running as a TTN node right now.
There’s cheap gateways available that are hard-coded to talk to TTN, and there’s expensive gateways available that let you run a private WAN. There just doesn’t seem to be cheap gateways available to run a private WAN.