Earlier quoted context omitted.
Which seems like a super easy fix for Twilio to implement. Don't allow SMS to premium rate numbers. If they can identify the premium numbers for billing, they should be able to identify them for blocking.
Down thread someone pointed out that their API allows you to set a max price: https://www.twilio.com/blog/2015/08/introducing-max-price.ht... Apparently a lot of people could really use that info.
I agree with other comments here. $0 is the minimum amount people should be willing to pay if they're not disputing charges or reporting fraud to the credit card networks / regulators.
Time is money, after all.