checkout shirtspace, or any site that lets you order shirts to print on. They're usually a few dollars each and you can get them in bulk in different colors. Different fabrics, styles, weights, etc. Literally shopping for tshirts by specs instead of look.

Bronson Mfg has some good solid shirts that are 100% cotton.

Tshirtwholesaler, try a few different shirt brands and styles out. There's so many that are plain white (or color) tees, only potential branding is against your neck on the inside of the shirt. I actually dontind having something there, because sometimes someone's like "Hey, what kind of shirt is that, it's soft, I like the cut, it wears nice," and then I direct them to the tag or print at the inside collar for information.

Hmmmm, sounds like advertising....

Very smart, giving money to a company and not using their product because it has a logo nobody will ever see...

YOU FORGOT THE SWOOSH BITCH you can almost hear the child laborers yelling at me.

I wish it was only a desirable brand problem. I used to get Skechers and not only have they gotten way too expensive for what they are (like, stay in your lane you're basically Payless Shoesource) but they put a bunch of tiny labels on their "propriety technology" now. Look at these ugly things. https://www.skechers.com/skechers-slip-ins-go-walk-workout-walker/217196_OLV.html

But so do the knockoffs