Re: If Huawei agreed an payment plan with Ericson
"I bet the original inventors of these patents got a one-time bonus of €1000 or so"
You seem a bit confused about how things work in the real world.
The original inventors got a full time job that paid a salary for the duration of the time it took to invent. The company that employed them took the risk of paying them all that time when it could have amounted to nothing. The company therefore rightfully owned the patent and got the profit from it, otherwise why would they employ them?
"Now some company that had nothing to do with the invention at all will get free money"
The company that had nothing to do with the invention paid for that patent. They got nothing for free. They thought they could make money from it. Otherwise, why would they buy it?
They paid the company who owned the patent, who obviously needed/wanted money upfront and therefore sold the patent. Otherwise, why would they sell it?