Absolutely. I had a non-vented replacement cap before I understood the system. On a long road trip the fuel pump would eventually act like it was sucking air. Every 100 miles or so I would stop and tighten everything but, coincidently I always stopped at service stations, at which time also I took the opportunity to top up with petrol.
The refuelling allowed air back into the sytem and off I went blindly thinking that my frantic tightening had done the trick!
BTW that cap was purchased from a supplier of AH parts. They should know better than to sell these things.