I found a place in Florence that I think readers would like, especially if they have an apartment, as we did. It's mainly for locals to buy table wine, bring or buy your own containers. You can buy a regular glass bottle for 1 euro, sample the various wines they have and make your choice. My favorite was the most expensive San Gimignano for 2 euro a bottle, which was excellent! They fill from large containers. Then just bring back the empties and they refill them.
It's DiVino, Via Taddea 6r, Firenze. Tel 055 2670588. Very close to the Mercato Centrale.
I have seen other such shops in Florence and Rome, but this happens to be one that I bought from and can vouch for their quality.
Jeff