People still answer the phone from unknown numbers?
Seriously, if I don't know the number it's going to VM. If important they'll leave a message or text / email me. If no message, I have my answer.
I assume all 866/888 numbers are SPAM and can also typically pick out robo calls because my cell phone area code (802) doesn't match the area code where I live (919) -- and spammers have started trying to fake you into picking up the phone by adopting your local area code so you think it's a local business calling (or maybe your kid's school or doctor)