Personaly I think some instructors have a ego problem by letting there students do such things. Why do something when there is not reason to? are you trying to prove something or show of to your instructing buds. Don't let one of your hazardous attitudes get one of your students.
Being comfortable with one's own judgement and abilities as an instructor is not a hazardous attitude. Are we going out and pushing people to solo at night, just for bragging rights? Come on. Give me a break. I'm saying if it makes things more convenient for the student, I'd be willing to give the training and endorsement. This has absolutely nothing to do with showing off to anyone.
"Why do something when there is not reason to?"
I think this question is getting to the root of the debate. It represents a general perspective a lot of pilots have when it comes to training. Some pilots aren't willing to step out of their comfort zone at all. They've been taught somewhere that activity XYZ is risky (might be true, might not), so they don't want to have anything to do with activity XYZ until they are absolutely forced to. That could apply to night flying, mountain flying, flying over top of an undercast, doing long (500+ mile) cross countries, spin training, etc.
I'm certainly not immune to it. You want to hear something funny? The first time I landed on grass was during my commercial checkride, to demo a soft field landing. And I was a little scared of it. I thought I might screw it up and dig the Arrow's nose into the sod. Through my previous training, it was a big no-no, mainly for insurance reasons, to operate off of anything that wasn't hard surfaced and at least 2500' long.
Was there any rational to my concern? None, whatsoever. It was an induced fear passed on to me by my previous instructors and flight school managers. I'm currently teaching off a grass runway and would be the first to tell students landing on a short grass runway is pretty much a non-event after doing it a few times. Heck...my students are surprised when they do their first landing on a "massive" 6000' paved runway!
You know, there's really no reason to do a lot of things in flying. But a lot of those unrequired activities are what make better pilots. There's no reason to let students go more than the bare minimum 50 miles out and 50 miles back on their solo cross countries. But what would that do to them if I limited my students to going no more than say, 60 miles, just because "there's no reason to" and I don't want the liability?
They'd probably get it in their head that flying more than 60 miles away is dangerous...risky...something they can't handle...they're just not ready yet...that's a big step....they really ought to get more training before going further away...
Heck no! When I endorse somebody to fly cross countries, I tell them I want them to do the first trip over the same route we've gone over together, but for trips after that, they can go wherever they want. It might cost them more, and take more time, to fly 150 miles out and 150 miles back, but if that's what they want to do, I'll let them. Because they're PIC, they've been trained on how to do it, and I want to build their confidence to actually be a pilot, not a little drone that only does what I tell them to do. I want to turn out proficient pilots who are capable of fully exercising the privileges they have...and if that means soloing at night, I'm ok with that.
But maybe that's just my hazardous attitude talking.