Nice, but I would never give out login details to a separate service. I mean, I see why it may be necessary.
Even if I trust your intentions, (which I never do, no offense) what about everyone who tries to go after the honeypot of account details in a presumably less secure location? What about everyone you may know or hire now or in the future?
I understand, you will have to take it up with the developer / service provider. I assume they have good intentions. :-)