You can spam-click the bottle dispenser button for faster payout.

[The LCD]

That is all. Sometimes I come there with a full backpack + inventory half full of bottles and have to sit there for a while. Spam clicking makes it go faster.

[Trogladonis]

I don't know if it is helpful or not but I've found that hitting the sort button when searching for bottles to accumulate them all into single stacks helps speed up collection somewhat.

[Garbo8000]

You don't have to drag the bottles over, just hold the key down.