Wow, you actually encounter people willing to take you up on #3 these days? They're either in love with your company or desperate for work.
(Every job I've held has had this in some form or other. I'd wager it's common in countries with termination rules that aren't quite so, uh, "at will" as the US'.)
I'm happy to pay higher hourly during the contract to compensate for the lack of benefits.
I'm happy to pay a (naive) employee more than they asked for because I know what the position is worth and have no interest in tricking them.
This isn't generosity, it's just good long-term business IMHO.