Given that most megachurches have extensive IT installations, would it make sense to give remote access to volunteers? If you trust these volunteers to come in on Sundays and work with expensive equipment, then why not trust them during the week? Some of these volunteers no doubt work with commercial implementations costing in the millions, so they are used to the equipment. And with the ubiquity of the Internet, they should be able to access any computer equipment from anywhere. What would really be the harm in giving the access? Nothing, since they already have it on Sundays.
However, access has to always be for a purpose. You could well insist that any access granted to a volunteer should have a well defined purpose. And that purpose should determine the level of access granted remotely. For example, suppose you had a volunteer who put together the slides for the song lyrics on Sundays. There is little reason to insist that they come in two hours before the service on Sunday mornings to type this in. That just doesn’t leave much room for proofreading, and you should always proofread anything that you display to the entire congregation – preferably by more than one pair of eyes! It would be better to have them type up the lyrics on Thursday mornings, following Wednesday night choir rehearsal. You could easily grant them access to the computer running the lyrics remotely, and they could type them up. Have someone else check the lyrics on Friday, just to be sure. And then you’re all set for Sunday morning! The volunteer is happier, not having to come in so early. And the staff has more confidence that they did it right; they could be the ones checking it on Fridays. And the service will go more smoothly, with less chance of a glitch.
Remote access for volunteers does make sense. It should have a purpose, and be tightly controlled. It can also be logged by the IT department, to monitor for abuse. However, it will make for a smoother service and happier volunteers serving the Kingdom!