For white T-shirts Costco make excellent ones. The material is heavy like the shirts you could buy forty years ago.

In a related whine, it is unbelievable to me that a decent zip front hoodie is 65 bucks!

I agree with your rant, but for a different reason.

I wear thick tees as tucked undershirts when I carry because I have a Talon Grip (love it) on the CZ and I carry IWB usually (skateboard tape + bare skin = ouch). My favorite is the Gildan V necks, but they don't come locally in more than a 3 pack. They're also white.