Don't drink any beer any more myself, stopped drinking the stuff completely about 4 years ago, but I don't think folks are able to do that here. Well, there might be some small breweries that might allow it but mostly they just bottle their beer in Holland, I think.
Maybe in Belgium (they have a lot of breweries.. smaller/bigger), here and there, one can do it 'yourself'. I know in France, Spain and other wine producing countries it's totally common practice to fill up your own brought 'package' with p/m cheap table wines though. Wine, it being without the pop, is an easier product to do that with/duh.
I used to take my bottles and bota bags to Chiponia, where they had a lot of producing bodegas, to refill. 
Chiponia? In Spain? You've once visited the place, PPK?
Um, together with a friend (and his lady), we started up a bodega in Amersfoort p/m 15 years ago. We were trying to sell Spanish wines and cavas we imported, um, p/m ½ of the stock, ourselves. This to restaurants, other stores and everyone who wished to buy a bottle. Blahiah, but after the first year, and after break even point was reached luckily, we.. well decided it was time to move on and closed the store.
Looking back, we should have gone for it 200% instead of the 75% we gave it. Yeah, there were reasons to go our separate ways but to close, 'retro-spec-ing' and stop all was a bit stupid, really.
Still have a bit of a soft spot for wines from the Valdepeñas region. A 'young' red from there.. nice.
