An article relating to this blog post on Finextra:
Fraudsters rigging Chip and PIN terminals to steal data - report
Hundreds of Chip and PIN terminals in shops and supermarkets across Europe have been rigged by criminals and used to steal shoppers' card details, according to US national counter-intelligence executi...
Every use of the PIN exposes it, and the exposure has a cost attached. For small value transactions, say less than 50 Pounds, it is probably not economically justified.
Moreover, establishements where most of the transactions are low value could probably use much cheaper terminals, that do not have PIN pads at all.
No PIN used, no PIN stolen.