I do trust it well enough, but I don't use it.

For starters, I don't want it to be too easy to spend money. If I want something, I should want it enough to pull my card out and type the number again.

Second, the auto-fill often doesn't work perfectly, so you need the card anyway.

Third, there's the slim chance it could be hacked. So why even take that chance when the only benefit is convenience