You could create a member with specified access to the admin control panel to look up the logs as example and just add a member.
Nevertheless, I can understand you, but a developer is responsible for handling the situation and I assume that I will speak for nearly all of them that we are not interested into your data or personal information of customers. Of course this will not change the case.
Lets try to be honest, we are testing all our applications multiply times (at least i do), if we do not run into any issue on that, we expect all is working fine. When someone now reports an issue it is on our end to clarify the situation, mostly only limited data is provided and it is a ping pong until we have collected up all our information we need. A quick access on the ACP is mostly easier.
Additionally, as longer as you programm, as less you trust anyone and anything. How many of the people purchasing apps and stuff like that you think have knowledge that is required to provide us detailed information? Guess why IPS also want full access, even to the server, to provide support...