I do. But usually early on before I start acquiring good gear from the armory and Craw. Thats how I got my Merc com, till Amory provided a perfect version. my Nades and shields, except for when I went for Wee Wee Super Booster.
As I keep playing and build more characters, I’ll be doing a lot more of the vendor farming.
My vendors of choice, Underdome. Lucky’s watering hole. that machine is usually good. There are others, but most are situational.