Yes, generally this is the case with any rear facing seat although as they get older, the seats are more upright (if you choose to stay rear facing, which is a good idea!) so they take up less space.
It was going to be my next comment that the car seat itself protrudes much further forward than the base does.
Do any of the bases fit with seatbelt? You could try, if approved (check car manual, and car seat fitting list) fitting the base in the middle back seat. As the top of the shell is curved, you may get some leeway there, where it can protrude between the front two seats, rather than into the back of the seats. Also, try having the front seat more upright.
You get more space in an Estate car, which perhaps is why they are thought of as family cars. We have a Suzuki Swift and my knees are pretty much rammed into the dashboard while we had the infant seat in there! It's better with our current seat, Joie 360 Spin, although still tight. But I can get a couple of clicks back. When DH gives a taller colleague a lift (not now obviously) he has to move the seat to the side to let him in there!
Are you on Facebook? There is a good page called Car Seat Advice UK, you can use the search box to look for people with your car, and see whether they have had the same problem and what they can recommend. There are also a few retailers on there who have fitted so many car seats they can often tell you off the top of their heads which are shorter front to back.