I run Google ads on my site that generate some income, but it isn't all that much. It could be more but I don't work at it like Google would like me to. And I have a donation button on my blog, through PayPal, that helps pay my expenses associated with maintaining my sites.
I suppose if I wanted to approach this as a business I could double my income from Google, but that would take the fun out of it for me. Many wine bloggers who do little more than review commercial wines receive quite a lot of wine shipped to them for review. I rarely mention commercial wines and have only received four bottles, I think, and I mentioned three of them. I have hundreds of bottles of my own wine to drink, so I don't need more.