Is it "gross" to go out without a bra on

Honestly I don't need a bra to feel held up. My boobs are a 32 b but bras just hurt my chest so much I dread wearing one. I only wear one when I go out in public and take it off immediately when I get into the car. Is it ok if I wear a t shirt with no bra to the grocery store or the park? You can tell I don't have a bra on but does it really matter? Bras hurt my chest so badly but society thinks I have to wear one. Yet my republican boyfriend insists it shouldn't matter what other people think and that I should just do me and not wear one at all.