Why don't some 2S LiPo packs include a balancing connector?
If a lithium-ion battery with more than one cell has no provision for balancing, it's a blatant safety risk. As a battery ages, one cell will drop in capacity faster than the other, causing the lower capacity cell to eventually overcharge (risk of fire!) during charging. Nobody but the very cheapest, least reputable sellers will sell you one.  



That said, this battery brings three wires to the combined charging/discharging/balancing connector (3-pin female JST-PH). 

It's just hard to see because one of the wires has white insulation, and the image background is white, so I manipulated the image a bit to change the background colour.  

  

While a separate balancing connector is better (it reduces the effect of the voltage drop caused by the charging current on the balancing measurements), a charger can still balance charge this pack, since it does have a connection to every series cell in the pack.