ook, whitney, i'll bite....please tell us why they get all mad. my best guess is this--money in hand right now is the only thing a collector wants, because promises are made and broken all the time. anyone can say "I'll send you a check tomorrow", but few people would actually do it. so, my guess is that a collector will lie and claim that "you can only pay with check by phone right now" to avoid getting a broken promise, and to get money in hand right now.
Of course, no intelligent person should ever give out their banking info over the phone to a company like Encore, they are a bunch of crooks. And in the past, they have cleaned out more money than they claimed was owed from people's bank accounts. So, if you ever intend to continue collecting, remember this--if you push that "you can only pay with check over the phone today, or we're suing" garbage, keep in mind that you could very well be responsible for someone being defrauded out of money that your collection company has no right to take.