So if you are going to a plush restaurant/ bistro, it’s not okay to wear a t-shirt, dirty jeans or deck shoes. You can wear that to a club or roadside café.
One does not have to cavort around savile row suits to be acceptable for such places. Dressing appropriately and elegantly can be relatively inexpensive and sets you apart as a citizen capable of respect for surroundings and other diners.
All you need is a proper dress shirt, cotton pants and oxford shoes. To add a little flair to your outfit try using an ascot, blazer or even a bowtie.