i dunno, prolly price!
seriously though, im not sure....
but, i know from using hobbucity for my lipo's amd using the LHS around here, theres some serous pricing issues...
for example, a TP 3s 2100 mAh pack at my local LHS is 100.00!!!! one hundred dollars! thats no freaking joke.
so, i goto hobby city and get 3s 20c 2200 mAh zippy packs for around 18.00 thats just retarded, eh?
and last summer i bought 3 outrage 6s 2500 mAh packs, i believe i paid 140.00 us for them each, and i got some 3000 mAh 6s packs from hobbycity for around 50.00 US each, and the outrage packs have all but one puffed on me since then! and the hobbycity packs are sill perfect.
i ONLY buy packs at hobbycity now. ;-)