I mean, say, you want a really camera, or a drone, and since those things are made in China, they are too expensive to buy. So you just go to Canada, buy the thing, unpack it from the packaging, and pretend like its just personal items. Just like a smartphone.
AFIAK, border agents usually don’t ask if you bought your phone in the US or from outside, they shouldn’t ask about other personal electronics, right?
Last time I crossed back into the US from Canada the agent gave my friend shit because she didn’t have a physical receipt for the purchase she made and couldn’t prove it was worth less than the threshold. Even though I live in a border city I rarely cross because the agents are such assholes