What is the problem?
If your question has to do with the legitimacy of stopping you in the first place (the mere implementation of a checkpoint) refer to the earlier post with the URL attached discussing the conditions for an upheld-as-constitutional checkpoint stop. Has to be programatic, non-discriminatory, for a valid purpose, etc.
If your question has to do with showing your license which contains more information than is required to "identify yourself," you're engaging in the exercise of a government authorized privilege (operating your vehicle on the public road), so yeah, you're required to show that you have the permit to do that.
The folks who seem to be saying "the government shouldn't be able to make me do anything I don't want to do" are correct in a way: Nobody forces you to operate your motor vehicle on the public road, or agree to abide by the rules that go along with exercising that privilege. Don't agree to show the police a card with your home address on it? Don't drive.