I don’t buy things online.
But IF I did, there’s no way I’d claim it. Ohio has a section where they ask you to declare online purchases, and pay sales tax on those items.
Screw them. They get enough of my money. I’ll keep every penny I can.
I recommend Amazon.com. You can literally find anything you want there. I never pay shipping, either.
You could keep all your money. You just have to lie on your income tax form, like you say you would if you bought things online. You could also find an employer who paid you under the table, and you could print up a fake tax-exempt letter to use when you shop so you could avoid all the sales tax.
All of these actions of course are illegal, and all have some risk of being caught.
Without knowing what your definition of "I can" is, it's hard to say what level you are really willing to go to. Did you must mean breaking laws where it is unlikely you will get caught?