Not true we will only get a temporary economic hit but the EU has SO much more to lose...
There has been exit movements growing all across the board, all of which have held off to observe brexit.
If we leave with with a deal that deal would obviously include more payments but when they end...do you think the EU are just going to accept that they have less funding now, NO! They are going to demand that money be made up by everyone else, which will only increase anti EU sentiment and fearing another exit, the EU will make it clear that any more exits will be met with harsh fines and punishment...Hopefully the other members will think twice about exiting lest they face the wrath of the EU!
But if we leave with no deal, and are fine...what kind of message will that send, it will be proof that an exit can be done, so the next country who tries it, will, obviously, get a punishment deal right off the bat, but if they look at us and see that we can just refuse and just leave bypassing that punishment deal...why not do that?
After this the EU will demand more funding to cover the loss, seeing where this is headed even more member states will start the exit process, and so on and so forth, until there is no one left...
Do you really think the EU want to take that risk?