>>Unless i was in serious financial trouble, or in a learning situation, i would never accept a contract that "allows for unpaid overtime".

At least in the UK the law specifically forbids working more than 48 hours a week, so it's pretty common to see contracts where you opt out of this regulation. Not because the company even intends to make you work overtime, but because if you happened to work more, even entirely out of your own free will, you could still sue the company for working more than 48 hours in a week. So it's a very common thing to add in contracts here.