"Bribe" is the wrong word to use in all these cases. Free education is a recognition that we all benefit from having an educated population; the NHS is a recognition that we all benefit from having a healthy population; those who advocate tax breaks do so (in most cases) because they think it will benefit the economy generally. This isn't bribery, just enlightened self-interest.
You might even think of it as paying forward some of the benefits (bribes, if you will) that you received. Or do you think your parents were profligate fools when they bribed you for your love with food, shelter, money, toys? I've no patience with that view of the world, especially when it's so selectively applied.
Tangentially (as I noted on FB the other day), Greg Mulholland's father was on Any Answers on Saturday, arguing that students should be registered to vote in their parents' constituencies rather than the university towns where they live. That way, they won't be able to gang up on poor Tory and Lib Dem candidates like Sir Julian Brazier and, er, Greg Mulholland. Hilariously, he began by saying how much he welcomed the fact that the young had decided to vote this time. He just wants to make sure that their vote won't count.