Buying a bike for travelling on?

[Gazz]

Been reading a book recently (general travel book), but when the guy is in Vietnam, he says that it is very popular for tourists to buy bikes at one end of Vietnam and ride to the other end and then sell the bike to another tourist who rides it back to top again (or vice versa).

(On a side note I was wondering how long these bikes will last since they will be Chinese crap and will never seen any service or maintenance in their lives).

However, it got me thinking: has anyone ever bought a bike abroad with the sole intentions of using it for one trip?

In addition to this, it also got me thinking: that since it is fairly cheap to buy flights to somewhere like Greece, and since Greece seems to have more bikes than cars (it seemed like this the last time I was in Athens).

How easy would it be to get a hold of a cheap bike in somewhere like Greece, register it in your name, insure it and ride it home (or at least through a couple of countries) and then sell on to someone when you get to the end of your trip?

Surely since both countries are in the EU, then we are all good mates here.