ABS is a pain to print without an enclosure, and ABS for the most part doesn't absorbs water also it's not as much of an issue with the final parts (aside from Nylon that can expand easily) but rather that moisture caught in the filament boiling during the extrusion which results in your print looking like a sponge.
It prints fine on my non-enclosed delta. My printer isn't anything special, it's just, like you said, water absorption by the filament is an issue if it's left out in the open.
The key is simply to keep the filament in a drybox before use. It doesn't need to be anything fancy- I use a 5-gallon Home Depot bucket, a small jar of Damp Rid (Calcium Chloride), and a seedling heater mat to keep things warm. It works great.
