0.00001 per day/per unique public IP or something!!
That is 0.0365BTC in 10 years. Full nodes obviously consume
way less energy than mining does, but put it another way: if making money was as easy as running a full node, then so many people would abuse it that Bitcoin's price would just crash at one point. I'd be stupid not to profit off this chance.
If the remuneration was, on the other hand, even lower, then nobody would run a full node for something insignificant.
And even if we wanted to add this remuneration for running full nodes, where would that money come from? Tx fees? How can we make sure Bitcoin's max supply sticks at 21M while we still run the same block reward, keep the fees low and still make the max supply be a long-term target?