Firstly there's way more positions that economics grads can go to in a IB than just IBD. In fact Econ grads are more suited to S&T anyway, but you could also go into things like risk, quant (if education is beyond an undergrad degree), economic research, sales, etc. All these beyond the middle and back office roles like operations, compliance, etc.
Beyond this, lots of economics grads go into consulting (strategy and management), economic consulting, being a civil service economist. Many also go into roles in the big4 or into management/strategy positions at FMCG firms (Heinz, coca cola, Proctor&Gamble, Unilever, Mondelez, Mars, etc). So there's lots of opportunities for economics grads, lots of choice but it's worth noting that these are high pay roles so the competition is fierce