Actually several of the Behringer mini mixers do have balanced outs, including the MXB1002, $109, the MX1604, $169. and the MX2004A, $249. I use my MXB1002 as a main mixer for a small outdoor system when I need everything to run off of battery power. I set up two Peavey Solo amps on stands (which are battery powered) and run the MXB to them each as left and right balanced lines to their balanced inputs. It works great for situations where you don't need tremendous volumn, and just want to balance the sound out. (We play a hammered dulcimer, harp, flute, guitar and banjo, and use Boss pedal inserts to add reverb and delay for the flute and harp).

But for a few extra bucks, you can overcome the cost of a DI, and following the excellent advice above, get a good sound at a relatively cheap price.