https://emvacceptedhere.com/ 
(Disclosure: it's my site.) It's based on user contributions and the occasional mass insert of all of a retailer's locations if I see any sort of news article or internal source.
BTW Target should be 100% chip enabled by the 17th if the source that I saw is accurate.
Debit card fraud liability for the cardholder is worse in practice than for credit cards. Sure you'll probably get your money back eventually but it's still your money that went away. This probably won't matter nearly as much once chip becomes more widespread.
If they don't already support chip-enabled cards it's likely they're running Apple Pay just like a normal credit card swipe. Supporting chip cards means they can detect that Touch ID or some other device authentication was used and suppress signature entirely regardless of the amount.
Usually $25-50 depending on the type of card and merchant.
You can steal the physical card, but that's nowhere near a significant problem in the US compared to card cloning. That's why banks aren't bothering with a PIN, at least for now. Since the chip itself protects against counterfeiting regardless of how a cardholder's verified, it's unfair to say that chip and signature provides no benefit at all.
In theory Visa's mandated that ticket machines and the like support chip and signature cards since July 1st. If you've traveled since the end of June I'm surprised you're still having significant problems. Can you tell us where exactly you've had problems since then?
Also my BofA debit card is still chip and signature internationally and at places in the US that don't support debit. If you really feel that you need a PIN I wouldn't rely on that as an option based on what
https://www.bankofamerica.com/privacy/faq/emv-chip-card-faq.go says. (Not to mention that there's a 3% fee every time you use it overseas.)