[bitxbitxbitcoin]

It's better to think of the node runners as the "coin voters" for anything democratic. Look at the Bitcoin vs Bitcoin Cash split for instance.

Participants of modern mining pools for all coins are arguably just in it for the money (and likely have subsidized or below average electricity rates).

Proof of work isn't a democratic process at all. The "math problem" that the miners are solving is providing a hash of the next published block of transactions (plus some other things). The protocol doesn't check every miner's solution and democratically choose the correct set of transactions to publish based on consensus. Instead, it's a lottery - it's just that it isn't economically cost effective to "buy lottery tickets" that attempt to publish an essentially alternate "history" to the blockchain.

There are multiple ways to buy beer using cryptocurrency - physical debit cards that draw from a deposited cryptocurrency balance at time of purchase using the current exchange rate, for instance. Kind of like how it works when you use your EU debit card to pay for a beer in the US using euros.